- They can be made out of soda ash and cream of tartar and some water. Make thousands of kV just by hitting a crystal!
- More info on Piezoelectrics -
- Piezoelectricity
- Jim Emery
- 4/3/97Contents
- 0.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
- 0.2 The Linear Piezoelectric Equations . . . . . . . . . . . . . . . 3
- 0.3 Piezoelectric Ceramics Constants and One Dimensional Equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
- 0.4 The Stress Form of The Piezoelectric Matrix . . . . . . . . . . 9
- 0.5 Three Systems of Notation For The Piezoelectric Equations:
- Physics (IRE), ABAQUS, and ANSYS . . . . . . . . . . . . . 11
- 0.6 Deriving the Tensor Stress Form of the Piezoelectric Equations
- From the Strain Form . . . . . . . . . . . . . . . . . . . . . . 14
- 0.7 Orthotropic Material . . . . . . . . . . . . . . . . . . . . . . . 16
- 0.8 Poling and Piezoelectric Ceramics . . . . . . . . . . . . . . . . 18
- 0.9 The Equality of Direct and Converse Piezo Coefficients . . . . 20
- 0.10 Typical Values of Piezoelectric Parameters . . . . . . . . . . . 21
- 0.11 Piezoelectric Current and Impedance From A Finite Element
- Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
- 0.12 Piezoelectric Cube Example . . . . . . . . . . . . . . . . . . . 24
- 0.13 Generating Ferroelectric Hysteresis Curves . . . . . . . . . . . 26
- 0.14 The Strain Hysteresis Curve . . . . . . . . . . . . . . . . . . . 26
- 0.15 Relaxors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
- 0.16 Electrostriction . . . . . . . . . . . . . . . . . . . . . . . . . . 27
- 0.17 The Conversion Program: pzansys.ftn . . . . . . . . . . . . . 27
- 0.18 Example: Parameter Conversion Using Compliance Components 28
- 0.19 Example: Parameter Conversion Using Four Independent Elasticity Components . . . . . . . . . . . . . . . . . . . . . . . . 31
- 0.20 Example, Orthotropic Elastic Constants . . . . . . . . . . . . 34
- 0.21 Program Listing of pzansys.ftn Program . . . . . . . . . . . 37
- 0.22 Location of Piezoelectric Information In ANSYS Manuals . . . 58
- i0.23 ANSYS Comparison For A Composite Piezoelectric Transducer: Example VM176. . . . . . . . . . . . . . . . . . . . . . 59
- 0.24 Piezoelectricity Bibliography . . . . . . . . . . . . . . . . . . . 61
- ii0.1 Introduction
- We shall show how to derive the stress form of the piezoelectric equations
- from the strain form, and we shall show how to find the clamped permittivity
- matrix from the unclamped matrix. These conversions are required for finite
- element programs because in such programs equations are solved for the
- elastic displacements, and so the strains rather than the stresses are the
- independent variables. We shall do the basic derivation three times in the
- following sections. We shall first treat the one dimensional equation. In
- later sections we shall treat the matrix case and the full tensor case. These
- derivations are conceptually the same.
- 0.2 The Linear Piezoelectric Equations
- A piezoelectric ceramic is a ferroelectric material. It exhibits hysteresis and
- has nonlinear behavior. When this material is poled (placed in a strong
- electric field), it attains a permanently polarized state. For a small variation
- in the electric field, it behaves approximately linearly near that state.
- The linear piezoelectric equations are written in two different forms. In
- the more common form, which is called the strain form, the strain tensor εij
- and the electric polarization vector Pi are each written as linear functions of
- the electric field vector Ei and the stress tensor σij
- . These equations are
- εij = Ekdkij + c
- ijkl
- σkl
- ,
- and
- Pi = 0χijEj + dijkσj k.
- The dijk are the components of the piezoelectric tensor (strain coefficients).
- The c
- ijkl
- are the components of the inverse elastic tensor. The constant 0
- is the permittivity of free space. The χij are the components of the electric
- susceptibility tensor. In the direct piezoelectric effect, when a piezoelectric
- material is put under a stress, the material becomes electrically polarized
- and surface charges appear. The direct piezoelectric effect is
- Pi = dijkσj k,
- which is obtained from the second equation, when the external electric field
- is zero.
- 3In the converse piezoelectric effect, when a piezoelectric material is put
- in an external electric field (voltages applied to electrodes), the material
- experiences a strain. The converse piezoelectric effect is
- εij = Ekdkij
- ,
- which is obtained from the first equation, when there are no external forces
- and the stress is zero.
- The fact that the coefficients for both the direct effect and the converse
- effect are the same is a consequence of conservation of energy. This fact can
- be established by a thermodynamic argument (See Nye). Because of various
- symmetries in the tensor indices, the equations have matrix forms. Let us
- define an index function f : (i, j)− > k that takes a pair of indices and
- produces a single index. The function f takes values as follows: f(1, 1) =
- 1, f(2, 2) = 2, f(3, 3) = 3, f(2, 3) = 4, f(1, 3) = 5, f(1, 2) = 6 The function is
- symmetric, f(i, j) = f(j, i), and so f(3, 2) = 4, f(3, 1) = 5, f(2, 1) = 6. This
- is the Physics and The Institute of Radio Engineers assignment function. We
- define this function with a table:
- f 1 2 3
- 1 1 6 5
- 2 6 2 4
- 3 5 4 3
- This index assignment is the one most often used in elasticity theory to
- convert the second rank stress and strain tensors to six component vectors.
- Although this is the usual convention, the following assignment defined by
- function g is used sometimes (ABAQUS).
- g 1 2 3
- 1 1 4 5
- 2 4 2 6
- 3 5 6 3
- A third index function is also used. The function, which we call h is used
- by the finite element program ANSYS.
- 4h 1 2 3
- 1 1 4 6
- 2 4 2 5
- 3 6 5 3
- Warning! These differences in index assignment will change the matrices
- such as c, d, e.
- The matrix components of the piezoelectric tensor are di,f(i,j) and are
- either equal to the tensor component itself, when i = j, or to twice the
- component. This will be explained below.
- There is a second form of the piezoelectric equations, which is called the
- stress form.
- The stress tensor σij and the electric displacement vector Di
- , are each
- written as linear functions of the electric field vector Ei and the strain tensor
- εij
- . These equations are
- σij = cijklεkl − Ekekij
- ,
- and
- Di = eijkεj k + ijEj
- .
- The cijkl are the components of the elastic tensor. The eijk are the components of the piezoelectric tensor (stress coefficients). The ij are the components of the permittivity tensor.
- These equations are suitable for finite element programs because in these
- programs the displacements and hence the strains are the independent variables, whereas the boundary conditions are given as force loadings, that is as
- stresses. It will be shown below that the piezoelectric stress coefficients and
- the strain coefficients are related as follows:
- eijk = cj klmdilm.
- Notation varies greatly in the field of piezoelectricity. In a following
- section we will summarize the notation used in physics, and in two finite
- element programs ABAQUS and ANSYS.
- 50.3 Piezoelectric Ceramics Constants and One
- Dimensional Equations
- The principal references for this section are: Jaffe, Cook and Jaffe, Piezoelectric Ceramics, and the Morgan Matroc document Guide To Modern
- Piezoelectric Ceramics.
- The original research on piezoelectric materials was conducted with parallel plate capacitors, and the problem was treated as one dimensional. So
- the strain form of the equations considered were
- ε = Ed + c−1
- σ
- P = 0χE + dσ,
- where the quantities are in the 3 direction. From the definition of the electric
- displacement
- D = P + 0E = 0(χ + 1)E + dσ =
- σ
- E + dσ.
- So we have an alternate form
- D =
- σ
- E + dσ.
- Here
- σ
- is the permittivity at constant stress (unclamped).
- The second set of piezoelectric equations (stress form) may be obtained
- from the first set (strain form). Solving the first equation for the stress, we
- have
- σ = cε − cdE = cε − eE.
- Making this substitution for σ in the alternate form of the second equation
- of the first set, we get the second equation of the second set.
- D =
- σ
- E + d(cε − eE) = E + eε,
- = (
- σ
- − de)E + dcε
- =
- ε
- E + eε,
- where the piezoelectric coefficient e = cd. Here
- ε
- is the permittivity at
- constant stress (unclamped).
- 6The coefficients may be defined as partial derivatives. For example,
- d = (
- ∂ε
- ∂E
- )σ,
- where the subscript σ means that ε is a function of E and σ, where σ is held
- constant in computing the partial derivative. Similarly we have
- d = (
- ∂P
- ∂σ
- )E
- The constant g is defined by
- g = (−
- ∂E
- ∂σ
- )ε = (
- ∂ε
- ∂D
- )σ.
- We have
- E =
- 1
- (D − dσ)
- so
- g = −(
- ∂E
- ∂σ
- )ε =
- d
- .
- The constant e is defined by
- e = −(
- ∂σ
- ∂E
- )ε = (
- ∂D
- ∂ε
- )E
- The poled ceramic is an orthotropic material with a plane of symmetry
- whose normal is in the poled direction. Further it is symmetric with respect
- to any rotation about the poling direction. Performing a reflection through
- the symmetry plane, some of the strain components and stress components
- are maintained in sign and some others are changed in sign. Writing the
- various components of stress as functions of strain, in the two coordinate
- systems, we find that the proper signs can be maintained only if some of the
- elastic coefficients are zero (see pp62-64 Sokolnikoff Mathematical Theory
- of Elasticity). Carrying out rotation transformations about the poling axis
- (3 direction) we find further conditions on the elasticity coefficients. We have
- only the following independent elastic coefficients (Jaffe et al, p20)
- c11, c33, c44, c12, c13.
- 7We have
- c22 = c11, c55 = c44, c66 = 2(c11 − c12), c23 = c13.
- Coefficients which are not in the upper 3-dimensional submatrix or on the
- main diagonal are zero.
- The independent piezoelectric coefficients are
- d33, d31, d15.
- We have
- d32 = d31, d24 = d15.
- All other coefficients are zero.
- The independent dielectric coefficients are
- K11, K33
- We have
- K22 = K11.
- All other coefficients are zero.
- The permittivity is
- ij = 0Kij
- .
- The electromechanical coupling constant is defined in terms of the ratio
- of stored electrical to stored mechanical energy. Let Qmech be the electrical
- energy converted to mechanical energy and let Qinput be the electrical energy
- input. Then the electromechanical coupling factor is
- k
- 2
- =
- Qmech
- Qinput
- .
- It is claimed (Jaffe et al p7) that the relation between the unclamped dielectric constant Kσ
- and the clamped dielectric constant Kε
- is
- K
- ε
- = K
- σ
- (1 − k
- 2
- ).
- Because 0 < k < 1, the clamped dielectric constant is smaller than the
- clamped constant
- Kε
- < Kσ
- .
- 80.4 The Stress Form of The Piezoelectric Matrix
- Given the strain form of the piezoelectric equations, we can convert to the
- stress form and give expressions for the three independent e tensor parameters. In matrix form we have
- ε = d
- T
- E + c−1
- σ
- P = 0χE + dσ
- From the first equation multiplying by the elasticity matrix c we have
- cε = cd
- T
- E + σ,
- so solving for the stress matrix σ we have
- σ = cε − cd
- T
- E
- = cε − eE,
- where the matrix e is defined as the product of c and the transpose of d
- e = cd
- T
- .
- We have
- e
- T
- = (cd
- T
- )
- T
- = c
- T
- d = cd
- The last equality follows because c is symmetric. From the second equation
- D = P + 0E = 0χE + dσ + 0E
- = 0(χ + I)E + dσ
- =
- σ
- E + dσ,
- where
- σ
- is the permittivity at constant stress (unclamped permittivity).
- Substituting the expression for the stress σ from above
- D =
- σ
- E + d(cε − eE)
- = (
- σ
- − de)E + dcε
- 9=
- ε
- E + e
- T
- ε,
- where
- ε
- =
- σ
- − de
- is the permittivity at constant strain (clamped permittivity). In the previous
- section we saw that the elastic matrix c has 5 independent parameters and
- d has three independent parameters. We have
- c =
-
-
-
-
-
-
-
-
- c11 c12 c13 0 0 0
- c12 c11 c13 0 0 0
- c13 c13 c33 0 0 0
- 0 0 0 c44 0 0
- 0 0 0 0 c44 0
- 0 0 0 0 0 2(c11 − c12)
-
-
-
-
-
-
-
-
- ,
- and
- d =
-
-
-
- 0 0 0 0 d15 0
- 0 0 0 d15 0 0
- d31 d31 d33 0 0 0
-
-
- .
- Then the piezoelectric stress matrix is
- e = cd
- T
- =
-
-
-
-
-
-
- c11 c12 c13 0 0 0
- c12 c11 c13 0 0 0
- c13 c13 c33 0 0 0
- 0 0 0 c44 0 0
- 0 0 0 0 c44 0
- 0 0 0 0 0 2(c11 − c12)
-
-
-
-
-
-
-
-
-
-
-
-
- 0 0 d31
- 0 0 d31
- 0 0 d33
- 0 d15 0
- d15 0 0
- 0 0 0
-
-
-
-
-
-
- =
-
-
-
-
-
-
-
-
- 0 0 c11d31 + c12d31 + c13d33
- 0 0 c12d31 + c11d31 + c13d33
- 0 0 c13d31 + c13d31 + c33d33
- 0 c44d15 0
- c44d15 0 0
- 0 0 0
-
-
-
-
-
-
-
-
- 10=
-
-
-
-
-
-
-
-
- 0 0 e13
- 0 0 e13
- 0 0 e33
- 0 e42 0
- e42 0 0
- 0 0 0
-
-
-
-
-
-
-
-
- So the three independent piezo e parameters are e13, e33, e42. (Warning! The
- e matrix is sometimes defined as the transpose of this e matrix.)
- Explicitly we have
- e13 = (c11 + c12)d31 + c13d33
- e33 = (c13 + c13)d31 + c33d33
- and
- e42 = c44d15.
- These equations are easily solved for d33, d31 and d15 in terms of the three
- independent e and five independent c coefficients.
- 0.5 Three Systems of Notation For The Piezoelectric Equations: Physics (IRE), ABAQUS,
- and ANSYS
- The index function f(ij), which maps two indices to one, in the way that
- is conventional in elasticity theory, was defined in the previous section, as
- was g(ij). Here is a table showing the notation most commonly used in
- physics (References, Nye, Auld, Cady, IRE (The Institute of Radio Engineers Standard) ANSYS Procedures p8-15, ), and in the finite element systems ABAQUS (Reference: Theory manual, section 3.10.1), and ANSYS
- (Reference: Theory manual, Piezoelectrics chapter).
- 11Vari abl e Physics ABAQUS ANSYS
- Electric Field Vector Ei Ei Ei
- Electric Polarization Vector Pi Pi Pi
- Electric Displacement Vector Di
- qi Di
- Stress Tensor σij σij σij
- Stress Vector σk = σf(ij)
- - Tk
- Strain Tensor εij εij
- -
- Strain Vector εk - Sk
- Electric Permittivity Tensor ij D
- φ
- ij
- ij
- Electric Susceptibility Tensor χij
- - -
- Elasticity Tensor cijkl Dijkl
- cijkl
- Elasticity Matrix cmn = cf(ij)f(kl) − cmn
- Inverse Elasticity Tensor c
- ijkl
- - c
- ijkl
- Piezoelectric Tensor (strain) di,jk d
- φ
- i,jk
- di,jk
- Piezoelectric Matrix (strain) di,m = di,f(j k) di,m = di,g(j k) di,m
- Piezoelectric Tensor (stress) ei,jk e
- φ
- i,jk
- ej k,i
- Piezoelectric Matrix (stress) ei,m = ei,f(j k)
- ei,m = ei,g(j k)
- em,i
- The engineering strain coefficients are written as γij
- . They differ from
- the εij
- , in that the shear coefficients are doubled in value.
- Note: the physics notation for eijk is defined in equation 8.40 of Auld. Nye
- does not introduce the piezoelectric e coefficients. The Cady book is very
- old and one can obtain piezoelectric constant notation only by implication.
- Note: The ANSYS definition of the e matrix and tensor is the transpose of
- the physics and ABAQUS definition. Thus the ANSYS e matrix is 6 by 3,
- whereas the physics e matrix is 3 by 6.
- The two ABAQUS tensor equations are:
- σij = Dijklεkl − e
- φ
- mijEm
- (or alternately: σij = Dijklεkl − Dijkld
- φ
- mkl
- Em)
- qi = e
- φ
- ijk + D
- φ
- ijEj
- .
- The ANSYS matrix equations are:
- T = cS − eE
- D = e
- T
- S + E.
- 12The Physics matrix equations are:
- σ = cε − e
- T
- E,
- D = eε + E.
- Again note that the ANSYS e definition and the physics e definition are
- transposes of one another.
- Here are the ANSYS matrices written out:
- T = σ =
-
-
-
-
-
- σ1
- σ2
- ...
- σ6
-
-
-
-
-
- S = ε =
-
-
-
-
-
- ε1
- ε2
- ...
- ε6
-
-
-
-
-
- E =
-
-
-
- E1
- E2
- E3
-
-
-
- D =
-
-
-
- D1
- D2
- D3
-
-
-
- c =
-
-
-
-
-
-
-
-
- c11 c12 c13 0 0 0
- c21 c22 c23 0 0 0
- c31 c32 c33 0 0 0
- 0 0 0 c44 0 0
- 0 0 0 0 c55 0
- 0 0 0 0 0 c66
-
-
-
-
-
-
-
-
- 13e =
-
-
-
-
-
-
- e11 e12 e13
- e21 e22 e23
- e31 e32 e33
- e41 e42 e43
- e51 e52 e53
- e61 e62 e63
-
-
-
-
-
-
- =
-
-
-
- 11 0 0
- 0 22 0
- 0 0 22
-
-
-
- We will show in the next section that (physics notation)
- eijk = cj klmdilm.
- 0.6 Deriving the Tensor Stress Form of the
- Piezoelectric Equations From the Strain
- Form
- We have already done this derivation in a previous section for the matrix
- forms of the piezoelectric equations. Here we will repeat this for the tensor
- forms of the equations. We start with the strain form of the piezoelectric
- equations
- εij = Ekdkij + c
- ijkl
- σkl
- ,
- and
- Pi = 0χijEj + dijkσj k.
- Let cpqij be the elasticity tensor. Because c
- is its inverse, we have
- cpqij
- c
- ijkl = δ
- p
- k
- δ
- q
- l
- .
- Then multiplying the first equation by cpqij and summing we get
- cpqijεij = cpqijEkdkij + cpqij
- c
- ijkl
- σkl
- ,
- 14which becomes
- cpqijεij = cpqijEkdkij + σpq.
- We let
- ekpq = cpqijdkij
- .
- Then
- σpq = cpqrsεrs − empqEm.
- The equation relating electric displacement D, electric polarization P, and
- the macro electric field E is
- Di = Pi + 0Ei
- .
- Substituting for the polarization from the second piezoelectric equation above,
- we have
- Di = 0χijEj + dijkσj k + 0Ei
- .
- We write this as
- Di = 0(χij + δij
- )Ej + dijkσj k
- =
- σ
- ijEj + dipqσpq,
- where
- σ
- ij
- is the zero stress (unclamped ) permittivity. Substituting our previously derived expression for the stress, we get
- Di =
- σ
- imEm + dipq(cpqrsεrs − empqEm)
- = (
- σ
- im − dipqempq)Em + dipqcpqrsεrs
- = eirsεrs +
- ε
- imEm,
- where
- ε
- im =
- σ
- im − dipqempq
- is the zero strain (clamped) permittivity. We have assumed that cpqrs = crspq.
- This is the case when the internal energy of the material is a function of the
- values σ, ε, D, and E, and not dependent on the path through which the
- state was reached, that is,when the internal energy is an exact differential in
- the thermodynamic sense. Therefore redefining the dummy indices, we have
- the stress version of the piezoelectric equations:
- σij = cijklεkl − Ekekij
- ,
- 15and
- Di = eijkεj k +
- ε
- ij
- Ej
- .
- The matrix forms of these equations are:
- σ = cε − e
- T
- E,
- D = eε +
- ε
- E.
- 0.7 Orthotropic Material
- For the basic equations of elasticity, see Jim Emery Elasticity, (See files:
- elastic.tex, elastic.ps).
- An orthotropic problem is one in which the material properties are symmetric with respect to 3 mutually orthogonal planes (See Sokolnikoff p62). A
- piezoelectric ceramic such as PZT is orthotropic, but has even more symmetry. It is invariant to any rotation about the poled axis. By applying various
- symmetry transformations, and invariance properties, one finds that many
- of the elastic constants must be zero. The elastic matrix becomes
- c =
-
-
-
-
-
-
-
-
- c11 c12 c13 0 0 0
- c21 c22 c23 0 0 0
- c31 c32 c33 0 0 0
- 0 0 0 c44 0 0
- 0 0 0 0 c55 0
- 0 0 0 0 0 c66
-
-
-
-
-
-
-
-
- .
- The inverse matrix is
- c
- = c−1
- =
-
-
-
-
-
-
-
-
- 1/E1 −ν21/E2 −ν31/E3 0 0 0
- −ν12/E1 1/E2 −ν32/E3 0 0 0
- −ν13/E1 −ν23/E2 1/E3 0 0 0
- 0 0 0 1/(2µ32) 0 0
- 0 0 0 0 1/(2µ31) 0
- 0 0 0 0 0 1/(2µ12)
-
-
-
-
-
-
-
-
- .
- The Poisson ratio, νij
- , is the ratio of the negative of the strain in the
- xj direction, to the strain in the xi direction, for a normal stress in the xi
- direction. For example, if the only nonzero stress component is σ1, then
- 16
-
-
-
-
-
- 1/E1 −ν21/E2 −ν31/E3 0 0 0
- −ν12/E1 1/E2 −ν32/E3 0 0 0
- −ν13/E1 −ν23/E2 1/E3 0 0 0
- 0 0 0 1/(2µ32) 0 0
- 0 0 0 0 1/(2µ31) 0
- 0 0 0 0 0 1/(2µ12)
-
-
-
-
-
-
-
-
-
-
-
-
- σ1
- 0
- 0
- 0
- 0
- 0
-
-
-
-
-
-
- =
-
-
-
-
-
-
-
-
- σ1/E1
- (−σ1ν12)/E1
- (−σ1ν13)/E1
- 0
- 0
- 0
-
-
-
-
-
-
-
-
- =
-
-
-
-
-
-
- ε1
- ε2
- ε3
- 0
- 0
- 0
-
-
-
-
-
-
- .
- So that
- ν12 =
- −ε2
- ε1
- ,
- and
- ν13 =
- −ε3
- ε1
- ,
- By the symmetry of c, we have
- νij/Ei = νj i/Ej
- .
- So there are three independent values of Poisson’s ratio. We can take these
- to be
- ν12, ν13, ν23,
- or
- ν21, ν31, ν32.
- 17For the case of poled piezoelectric ceramics poled in the 3 direction, the best
- choice is
- ν21, ν31, ν32.
- It is clear that in that case
- ν31 = ν32,
- so that there are only two independent poisson ratio’s, which we may take
- as
- ν21, ν31.
- Also we see that ν31 is the poisson ratio stated for piezoceramics and is said
- to be about
- .31
- If the engineering strain vector is used then the shear strains are twice the
- physics shear strains, so that the 2 multiplying a shear modulus is suppressed.
- The engineering shear strain is equal to the shear angle, the physics shear
- strain is equal to one half the angle.
- The notation for shear modulus µij depends upon which of the index
- mappings f or g is used in assigning the stress-strain tensor indices to the
- vector indices.
- 0.8 Poling and Piezoelectric Ceramics
- See:
- Newnham R E, Trolier-McKinstry S,Giniewicz J R
- Piezoelectric, Pyroelectric and Ferroic Crystals
- J. Material Education, 15, 189-223 (1993),
- (reprint: Penn State MRL annual report to ONR 1994, Appendix 1)
- For the nature of the strain vs electric field curve, the nature of domains
- in PZT, and the morphotropic phase boundary between tetragonal PbTiO3
- and rhombohedral PbZrO3 ferroelectric phases, see:
- Subbarao E C, Srikanth V,Cao W, Cross L E
- Domain Switching And Microcracking During
- Poling Of Lead Zirconate Titonate Ceramics
- 18Ferroelectrics 1993 V 145 pp. 271-281
- (reprinted: Materials For
- Adaptive Structural Acoustic Control, Office
- Of Navel Research, Penn State Materials
- Research Laboratory, L. Eric Cross ed, V1 1994, appendix 15).
- The morphrotropic phase boundary is the boundary between two different structures of the piezoelectric material. We note that “morph” is a
- root meaning form, and “trop” is a root meaning to turn or change. Hence
- morphotropic means: a change in form.
- Consider the equation
- Pi = dijσj
- .
- Let the poling direction be the z axis. Then the domains will be randomly
- directed in the xy plane. Hence the ceramic will be orthotropic relative to
- the xy plane. Because of this symmetry, the piezoelectric matrix takes the
- form (see Jaffe, Cook, Jaffe Piezoelectric Ceramics, p20)
- d =
-
-
-
- 0 0 0 0 d15 0
- 0 0 0 d24 0 0
- d31 d32 d33 0 0 0
-
-
- .
- =
-
-
-
- 0 0 0 0 d15 0
- 0 0 0 d15 0 0
- d31 d31 d33 0 0 0
-
-
- .
- The elasticity tensor takes the form
- c =
-
-
-
-
-
-
-
-
- c11 c12 c13 0 0 0
- c12 c22 c13 0 0 0
- c13 c13 c33 0 0 0
- 0 0 0 c44 0 0
- 0 0 0 0 c44 0
- 0 0 0 0 0 2(c11 − c12)
-
-
-
-
-
-
-
-
- .
- The dielectric tensor is
-
-
- K1 0 0
- 0 K1 0
- 0 0 K3
-
-
- .
- 19Suppose we have d31 = d32, d33, d15 = d24,and dij = 0, otherwise. Then we
- have
- d311 = d31,
- d322 = d32,
- d333 = d33,
- d113 = d15/2,
- d131 = d15/2,
- d223 = d24/2,
- d232 = d24/2,
- and dijk = 0 otherwise.
- 0.9 The Equality of Direct and Converse Piezo
- Coefficients
- This equality may be shown by applying the first and second laws of thermodynamics. Let the stress coefficients σij
- , the electric field components Ei and
- the temperature T be the state variables. Then write differential expressions
- for the strain deij
- , the electric displacement dDi
- , and the entropy dS. Write
- the internal energy change as
- dU = σijdeij + EidDi + T dS.
- Introduce the function
- Φ = U − σij eij − EiDi − T S.
- Compute the differential of Φ using the last two equations, and also write it
- in the general partial derivative form. Then equate the partial derivatives to
- coefficients of the equations. For example
- ∂Φ
- ∂Ei
- = −Di
- .
- Differentiate to equate derivatives of eij
- , Di
- , or S to second order partial
- derivatives of Φ. This shows for example that the coefficients in the direct
- piezoelectric effect are equal to the coefficients of the converse piezoelectric
- effect. See Nye p179.
- 200.10 Typical Values of Piezoelectric Parameters
- Dielectric constant
- K = 200 =
- 0
- 0 = 8.85 × 10
- −12
- farad/meter.
- KT
- dielectric constant at constant stress. KS
- dielectric constant at zero
- strain (constrained piezoelectric coefficient)
- d33 = 200 × 10−12
- coulomb/newton (or meter/volt).
- d31 = −100 × 10−12
- coulomb/newton (or meter/volt).
- d15 = 400 × 10−12
- coulomb/newton (or meter/volt).
- gij voltage coefficients.
- kij = gij
- Poisson’s ratio is approximately .31 for all ceramics. Curie temperature
- Tc = 300.
- fr = resonant frequency. Typical value is 70 kHz.
- Panasonic motor.
- Operating voltage 22 volts.
- Rated output 1 watt.
- Torque 250 gf.cm (gf gram force)
- 250 gf cm (pound/454 gf)(inch/2.54 cm)(16 ounce/pound) = 3.47 inch.ounce
- Current .4 amp at 5 to 10 volts
- Input power 2 to 4 watts
- Voltage of control circuit 12 volts
- 250 g.cm (kg/1000 g)(9.8 m/s.s)(m/100 cm) = .0245 N.m
- Angular velocity = 4002π/(min)(min/60sec) = 10.47(1/s)
- Power = (.0245)(10.47) = .2565 watt
- Speed 400 rpm, noload 600 rpm.
- fa = antiresonant frequency (parallel resonance)
- Electromagnetic coupling constant
- k = (electrical energy stored)/(mechanical energy stored).
- 21kp = .2 to .8 = planar coupling factor of a thin disk.
- Qm = quality factor.
- Example: Thickness
- l = .030inches = 7.63 × 10−4
- m
- v = 400volts.
- E = v/l = 3.67 × 10
- 6
- v/m.
- e = dE = (200 × 10−12
- )(3.67 × 10
- 6
- ) = 7.34 × 10−4
- .
- ∆z = el = 22µinches
- 0.11 Piezoelectric Current and Impedance From
- A Finite Element Calculation
- Let D be the electric displacement and ρ the charge density. We can use one
- of Maxwell’s equations
- ∇ · D = ρ,
- to show that the surface charge density on a conductor equals the normal
- component Dn of D outside of the conductor. We enclose a conducting
- surface with a thin pillbox of area A, volume V , and thickness ∆t. The
- charge contained in the volume is Aτ where τ is the surface charge density.
- Then letting ∆t go to zero, we have
- Aτ =
- V
- ρdV =
- V
- ∇ · DdV =
- ∂ V
- D · nds → D · nA.
- Then the charge density is
- τ = D · n = Dn.
- We compute the nodal strains εij
- from the nodal displacements ui at a
- face of an element.
- From the finite element nodal potentials φn, we compute derivatives of
- the shape functions, and then the gradient of the potential. Then we obtain
- the electric field Ei as the negative gradient of the potential,
- E = −∇φ.
- 22We compute the electric displacement from the piezoelectric equation
- Di = eijkεj k + KijEj
- .
- Then we compute the normal component Dn. This gives the surface charge
- density. Multiplying by the area A, we get the charge q. We sum up the
- charges on the boundaries of the elements to get the total electrode charge.
- If we calculate the charge as a function of time, we can fit it to a function
- Q0 cos(ωt + ψ),
- and thus to the real part of the exponential
- Q0 exp(j(ωt + ψ)).
- Differentiating with respect to time we get the current
- I = I0 exp(j(ωt + ψ)).
- Then if V is the applied voltage, the impedance is
- Z = V /I .
- We can also compute energy storage and dissipation in the finite element
- model, and relate it to energy storage and dissipation in an equivalent circuit.
- We can obtain or compute the energy density of the electric field
- D · E
- 2
- ,
- the elastic strain energy, the kinetic energy, heat dissipation, and frictional
- contact energy. The kinetic energy will correspond to inductor energy in
- the equivalent circuit, the strain energy and the electric field energy will
- correspond to capacitive energy, and the dissipation energy will correspond
- to a resistance loss. If the energies correspond, then the equivalent circuit is
- valid.
- 230.12 Piezoelectric Cube Example
- Consider a piezoelectric cube of side a. Let thin metal plates be located at
- z = 0 and z = a. Let there be a voltage V on these plates. Let there be a
- horizontal compressive forces F in the y direction acting on the y = 0, and
- the y = a faces of the block. The electric field is
- E =
-
-
-
- E1
- E2
- E3
-
-
- =
-
-
-
- 0
- 0
- V /a
-
-
-
- The stress is
- σ =
-
-
-
-
-
-
- σ1
- σ2
- σ3
- σ4
- σ5
- σ6
-
-
-
-
-
-
- =
-
-
-
-
-
-
- F /a
- 2
- 0
- 0
- 0
- 0
- 0
-
-
-
-
-
-
- .
- An average dielectric constant for PZT is
- K = 200 =
- o
- = 1 + χ.
- We have
- 0 = 8.85 × 10
- 10
- (C
- 2
- /N M2
- ).
- Then the permittivity is
- = 1.77 × 10−9
- .
- If we take the material to be isotropic, the polarization equation becomes
- P = 0χE +
-
-
-
- 0 0 0 0 d15 0
- 0 0 0 0 d25 0
- d31 d32 d33 0 0 0
-
-
-
-
-
-
-
-
-
-
-
- σ1
- σ2
- σ3
- σ4
- σ5
- σ6
-
-
-
-
-
-
-
-
- We have
- d31 = d32 = −100 × 10−12
- C/N or M/V
- 24d33 = 2100 × 10−12
- d51 = d15 = 400 × 10−12
- Because only σ1 is nonzero, we have
- P = 0χE +
-
-
-
- 0
- 0
- d31σ1
-
-
- .
- Then
- P3 = 0χE3 + d31σ1
- D = 0E + P.
- D3 = 0(1 + χ)E3 + d31σ1 = 0K E3 + d31σ1.
- The surface charge on the z = a face is
- Q = D3a
- 2
- .
- The strain is
- e =
-
-
-
-
-
-
-
-
- 0 0 d31
- 0 0 d32
- 0 0 d33
- 0 d25 0
- d15 0 0
- 0 0 0
-
-
-
-
-
-
-
-
-
-
-
- E1
- E2
- E3
-
-
- +
-
-
-
-
-
-
-
-
- c11 c12 c13 0 0 0
- c21 c22 c33 0 0 0
- c31 c32 c33 0 0 0
- 0 0 0 c44 0 0
- 0 0 0 0 c55 0
- 0 0 0 0 0 c66
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
- σ1
- σ2
- σ3
- σ4
- σ5
- σ6
-
-
-
-
-
-
-
-
- So the nonzero elements of the strain are
- e1 = d31E3 + σ1c11 = d31E3 +
- σ1
- ξ
- ,
- e2 = d32E3 + σ1c21 = d32E3 −
- σ1ν
- ξ
- ,
- e3 = d33E3 + σ1c31 = d33E3 −
- σ1ν
- ξ
- ,
- where ξ is Young’s modulus, and ν is Poisson’s ratio.
- 250.13 Generating Ferroelectric Hysteresis Curves
- Suppose we arrange two capacitors in series, one C1 containing a ferroelectric
- dielectric, and the second C2 a nonferroelectric dielectric. Let us connect in
- series an alternating high voltage source. Let V1 be the voltage across capacitor C1. This is a measure of the E field in the ferroelectric capacitor C1. The
- charge on the plates of C1 is proportional to the D field (actually the D field
- is equal to the surface charge density). But the charge on C1 is equal to the
- charge on C2 and moves from C1 to C2 and back again during a cycle of the
- applied alternating voltage. But the second capacitor is nonferroelectric and
- its dielectric is linear, so that the voltage V2 across the second capacitor is
- proportional to charge and hence to the D field of the ferroelectric capacitor.
- Therefore, if we connect V1 across the horizontal plates of an oscilloscope,
- and V2 across the vertical plates, we will see the hysteresis curve. The polarization field will be approximately equal to D, since the permittivity for
- the ferroelectric is much larger than the permittivity of free space 0.
- (I think this is close to the method given by Sawyer and Tower, see
- bibliography.)
- 0.14 The Strain Hysteresis Curve
- The strain vs electric field curve for a piezoelectric ceramic is a butterfly
- curve with the strain always of one sign, and the curve lying in the positive
- upper half plane.
- 0.15 Relaxors
- A relaxor ferroelectric has some of the properties of a normal ferroelectric,
- but is not so permanently polarized and has a very narrow hysteresis loop.
- When the field is removed, the material almost returns to an unpolarized
- state. It requires a bias field.
- See:
- Cross L Eric
- Relaxor Ferroelectrics: An Overview
- Ferroelectrics, 1994 v151 pp. 305-320
- 26(reprinted: annual report 1994 from MRL at Penn State to ONR v1 p305)
- 0.16 Electrostriction
- Electrostriction is an internal stress caused by the force of the electric field on
- charges. It occurs in all materials, not just piezoelectric ones. A computation
- shows it to be related to the gradient of the dielectric constant, and in practice
- the stress is proportional to the square of the electric field intensity. It is very
- hard to measure, since the force can be masked by the force due to the free
- charges on the capacitor plates.
- Notes and references to electrostriction: Wert, Thomson Physics of
- Solids, p. 321. Julius Adams Stratton, Electromagnetic Theory, pp149-
- 151. Panofsky and Philips Classical Electricity and Magnetism p.95,
- As a term of an equation. Maxwell stress tensor. Classical derivation. The
- treatment in Panofsky and Phillips is based on the treatment in Becker:
- (formerly called Becker and Abraham) Electromagnetic Fields and Interactions p. 134. In Jaffe: Piezoelectric Ceramics, Electrostriction is
- mentioned on pages 15 and 78. He relates electrostriction to domain reversal. Jaffe says that the effect is significant only for ferroelectrics above the
- Curie point. Cady: Piezoelectricity defines electrostriction to be that effect that is proportional to E
- 2
- . See pages 4, 198, 199, 614. Cady states
- that electrostriction is only significant for fields above 20,000 volts per cm.
- See also Auld, Acoustic Fields and Waves in Solids, volumes I and II,
- who presents a nice one dimensional model of the piezoelectric effect on p265.
- 0.17 The Conversion Program: pzansys.ftn
- This program does the conversion calculations derived in the previous sections. It requires as input the d parameters, and either the elasticity matrix,
- or its inverse. It computes the e parameters, and computes the clamped
- permittivity (strain constant) from the unclamped permittivity. It generates
- material property cards for the ANSYS program. We list the program in a
- later section. The next sections illustrate the operation of the program.
- 270.18 Example: Parameter Conversion Using
- Compliance Components
- yonada:/users/u51195 $ pzansys
- Reference: Jim Emery "Piezoelectricity",
- Document location:/u51195/ps/piezoelc.ps,piezoelc.tex
- Anonymous FTP: ftp.os.kcp.com /pub/emery/
- Units are metric: Newton, Meter, Kilogram
- stress: Newton/M^2 (Pascals)
- Young’s Modulus: Pascals
- Elasticity coefficients: Pascals
- Enter piezoelectric d constants (coulomb/newton)
- The IRE convention for piezoelectric labeling is used
- Type <return> for default value
- Enter d33 [ 2.0000000000000001E-10]
- Enter d31 [ -1.0000000000000000E-10]
- Enter d15 [ 4.0000000000000001E-10]
- d matrix=
- 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.4000E-09 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.4000E-09 0.0000E+00 0.0000E+00
- -0.1000E-09 -0.1000E-09 0.2000E-09 0.0000E+00 0.0000E+00 0.0000E+00
- Do you want to see the nonzero components
- of the 27 d tensor components? [n]
- Define the elasticity matrix or compliance matrix:
- (1)Use elastic constants to define compliance
- for orthotropic material, using Young’s moduli,
- Poissons ratios, and Shear Moduli.
- (2)Use the five components of the elastic matrix
- c11,c33,c44 (c44 is ANSYS c66),c12,c13,
- for a z-poled ceramic.
- (Note: c22=c11, c55=c44, c66=2(c11-c12),c23=c13,
- and c_{23}=c_{13}. Coefficients which are
- not in the upper 3-dimensional submatrix,
- not on the main diagonal, are zero.
- (3)Use the five components of the compliance matrix
- s11,s33,s44 (s44 is ANSYS s66),s12,s13,
- for a z-poled ceramic.
- (Note: s22=s11, s55=s44, s66=2(s11-s12),s23=s13,
- and s_{23}=s_{13}. Coefficients which are
- not in the upper 3-dimensional submatrix,
- not on the main diagonal, are zero.
- type <return> for default selection: [1]
- Enter the orthotropic elastic constants
- for a coordinate system in the principle directions
- Enter Young’s Modulus, in x [ 0.12800E+12]
- 28Enter Young’s Modulus, in y [ 0.12800E+12]
- Enter Young’s Modulus, in z [ 0.11000E+12]
- Enter ANSYS Poisson ratios (Theory sec. 2.1)
- Enter Major Poisson ratio prxy[ 0.30000 ]
- Enter Major Poisson ratio prxz[ 0.41976 ]
- Enter Major Poisson ratio pryz[ 0.41976 ]
- Enter shear modulus g23 [ 0.52000E+11]
- Enter shear modulus g13 [ 0.52000E+11]
- Enter shear modulus g12 [ 0.12200E+12]
- Compliance matrix (elasticity inverse) cinv=
- 0.7813E-11 -0.2344E-11 -0.3279E-11 0.0000E+00 0.0000E+00 0.0000E+00
- -0.2344E-11 0.7813E-11 -0.3279E-11 0.0000E+00 0.0000E+00 0.0000E+00
- -0.3279E-11 -0.3279E-11 0.9091E-11 0.0000E+00 0.0000E+00 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.1923E-10 0.0000E+00 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.1923E-10 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.8197E-11
- Note: In ANSYS components 4,5,6 are permuted
- (A different mapping from tensor to vector is used):
- ANSYS 44 is 66
- ANSYS 55 is 44
- ANSYS 66 is 55
- The five independent compliance coeficients are:
- s11= 0.78125000E-11
- s33= 0.90909091E-11
- s44= 0.19230769E-10
- s12=-0.23437500E-11
- s13=-0.32793388E-11
- Computing inverse matrix
- Elasticity matrix =
- 0.2104E+12 0.1119E+12 0.1163E+12 0.0000E+00 0.0000E+00 0.0000E+00
- 0.1119E+12 0.2104E+12 0.1163E+12 0.0000E+00 0.0000E+00 0.0000E+00
- 0.1163E+12 0.1163E+12 0.1939E+12 0.0000E+00 0.0000E+00 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.5200E+11 0.0000E+00 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.5200E+11 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.1220E+12
- Orthotropic constants from compliance matrix:
- Young’s Modulus 1= 0.12800000E+12
- Young’s Modulus 2= 0.12800000E+12
- Young’s Modulus 3= 0.11000000E+12
- Major Poisson ratio prxy= 0.30000000
- Major Poisson ratio prxz= 0.41975537
- Major Poisson ratio pryz= 0.41975537
- Shear Modulus g23= 0.52000000E+11
- Shear Modulus g13= 0.52000000E+11
- Shear Modulus g12= 0.12200000E+12
- 29Do you want to see the nonzero components
- of the 81 elasticity tensor components of c? [n]
- piezoelectric (stress) tensor coefficients
- Do you want to see the nonzero components
- of the 27 piezoelectric tensor components of e? [n]
- Piezoelectric e matrix=
- 0.0000E+00 0.0000E+00 -8.977
- 0.0000E+00 0.0000E+00 -8.977
- 0.0000E+00 0.0000E+00 15.52
- 0.0000E+00 20.80 0.0000E+00
- 20.80 0.0000E+00 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00
- Second calculation:
- e13= -8.977066554171117
- e33= 15.52345455897376
- e42= 20.80000000000000
- Note: ANSYS e rows are permuted
- ANSYS row 4 is row 6
- ANSYS row 5 is row 4
- ANSYS row 6 is row 5
- ANSYS Piezoelectric e matrix=
- 0.0000E+00 0.0000E+00 -8.977
- 0.0000E+00 0.0000E+00 -8.977
- 0.0000E+00 0.0000E+00 15.52
- 0.0000E+00 0.0000E+00 0.0000E+00
- 0.0000E+00 20.80 0.0000E+00
- 20.80 0.0000E+00 0.0000E+00
- d times e =
- 0.8320E-08 0.0000E+00 0.0000E+00
- 0.0000E+00 0.8320E-08 0.0000E+00
- 0.0000E+00 0.0000E+00 0.4900E-08
- Enter the unclamped dielectric constant K11
- [ 1300.0000 ]
- Enter the unclamped dielectric constant K33
- [ 1000.0000 ]
- Unclamped electric permitivity tensor=
- 0.1151E-07 0.0000E+00 0.0000E+00
- 0.0000E+00 0.1151E-07 0.0000E+00
- 0.0000E+00 0.0000E+00 0.8850E-08
- Clamped electric permitivity tensor=
- 0.3185E-08 0.0000E+00 0.0000E+00
- 0.0000E+00 0.3185E-08 0.0000E+00
- 0.0000E+00 0.0000E+00 0.3950E-08
- Enter density Kg/m^3 [7500]
- /COM
- /COM Material properties
- /COM Young’s Moduli
- EX, 2, 0.12800000E+12
- EY, 2, 0.12800000E+12
- EZ, 2, 0.11000000E+12
- 30/COM ANSYS "Major" Poisson ratios
- PRXY, 2, 0.30000000
- PRXZ, 2, 0.41975537
- PRYZ, 2, 0.41975537
- /COM Density Kg/m^3
- /COM DENS, 2, 0.75000000E-02
- /COM clamped Permitivities
- MP,PERX, 2, 0.31850000E-08
- MP,PERY, 2, 0.31850000E-08
- MP,PERZ, 2, 0.39498958E-08
- /COM ANSYS Piezoelectric "e" matrix
- TB,PIEZ,3
- TBDATA, 3, -8.9770666
- TBDATA, 6, -8.9770666
- TBDATA, 9, 15.523455
- TBDATA, 14, 20.800000
- TBDATA, 16, 20.800000
- 0.19 Example: Parameter Conversion Using
- Four Independent Elasticity Components
- yonada:/users/u51195 $ pzansys
- Reference: Jim Emery "Piezoelectricity", (piezoelc.ps)
- Document location:/u51195/ps/piezoelc.ps,piezoelc.tex
- Anonymous FTP: ftp.os.kcp.com /pub/emery/
- Units are metric: Newton, Meter, Kilogram
- stress: Newton/M^2 (Pascals)
- Young’s Modulus: Pascals
- Elasticity coefficients: Pascals, and so on)
- Enter piezoelectric d constants (coulomb/newton)
- The IRE convention for piezoelectric labeling is used
- Type <return> for default value
- Enter d33 [ 2.0000000000000001E-10]
- Enter d31 [ -1.0000000000000000E-10]
- Enter d15 [ 4.0000000000000001E-10]
- d matrix=
- 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.4000E-09 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.4000E-09 0.0000E+00 0.0000E+00
- -0.1000E-09 -0.1000E-09 0.2000E-09 0.0000E+00 0.0000E+00 0.0000E+00
- Do you want to see the nonzero components
- of the 27 d tensor components? [n]
- Define the elasticity matrix or compliance matrix:
- (1)Use elastic constants to define compliance
- for orthotropic material, using Young’s moduli,
- Poissons ratios, and Shear Moduli.
- (2)Use the five components of the elastic matrix
- 31c11,c33,c44 (c44 is ANSYS c66),c12,c13,
- for a z-poled ceramic.
- (Note: c22=c11, c55=c44, c66=2(c11-c12),c23=c13,
- and c_{23}=c_{13}. Coefficients which are
- not in the upper 3-dimensional submatrix,
- not on the main diagonal, are zero.
- (3)Use the five components of the compliance matrix
- s11,s33,s44 (s44 is ANSYS s66),s12,s13,
- for a z-poled ceramic.
- (Note: s22=s11, s55=s44, s66=2(s11-s12),s23=s13,
- and s_{23}=s_{13}. Coefficients which are
- not in the upper 3-dimensional submatrix,
- not on the main diagonal, are zero.
- type <return> for default selection: [1]
- 2
- Enter c11 [ 0.13200E+12]
- Enter c33 [ 0.11500E+12]
- Enter c44 (ANSYS c66) [ 0.52000E+11]
- Enter c12 [ 0.71000E+11]
- Enter c13 [ 0.73000E+11]
- Elasticity matrix c=
- 0.1320E+12 0.7100E+11 0.7300E+11 0.0000E+00 0.0000E+00 0.0000E+00
- 0.7100E+11 0.1320E+12 0.7300E+11 0.0000E+00 0.0000E+00 0.0000E+00
- 0.7300E+11 0.7300E+11 0.1150E+12 0.0000E+00 0.0000E+00 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.5200E+11 0.0000E+00 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.5200E+11 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.1220E+12
- Note: In ANSYS components 4,5,6 are permuted
- ANSYS 44 is 66
- ANSYS 55 is 44
- ANSYS 66 is 55
- Compliance matrix=
- 0.1273E-10 -0.3665E-11 -0.5754E-11 0.0000E+00 0.0000E+00 0.0000E+00
- -0.3665E-11 0.1273E-10 -0.5754E-11 0.0000E+00 0.0000E+00 0.0000E+00
- -0.5754E-11 -0.5754E-11 0.1600E-10 0.0000E+00 0.0000E+00 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.1923E-10 0.0000E+00 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.1923E-10 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.8197E-11
- Orthotropic constants from compliance matrix:
- Young’s Modulus 1= 0.78561263E+11
- Young’s Modulus 2= 0.78561263E+11
- Young’s Modulus 3= 0.62497537E+11
- Major Poisson ratio prxy= 0.28788955
- Major Poisson ratio prxz= 0.45203533
- Major Poisson ratio pryz= 0.45203533
- Shear Modulus g23= 0.52000000E+11
- Shear Modulus g13= 0.52000000E+11
- Shear Modulus g12= 0.12200000E+12
- 32Do you want to see the nonzero components
- of the 81 elasticity tensor components of c? [n]
- piezoelectric (stress) tensor coefficients
- Do you want to see the nonzero components
- of the 27 piezoelectric tensor components of e? [n]
- Piezoelectric e matrix=
- 0.0000E+00 0.0000E+00 -5.700
- 0.0000E+00 0.0000E+00 -5.700
- 0.0000E+00 0.0000E+00 8.400
- 0.0000E+00 20.80 0.0000E+00
- 20.80 0.0000E+00 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00
- Second calculation:
- e13= -5.700000000000001
- e33= 8.400000000000000
- e42= 20.80000000000000
- Note: ANSYS e rows are permuted
- ANSYS row 4 is row 6
- ANSYS row 5 is row 4
- ANSYS row 6 is row 5
- ANSYS Piezoelectric e matrix=
- 0.0000E+00 0.0000E+00 -5.700
- 0.0000E+00 0.0000E+00 -5.700
- 0.0000E+00 0.0000E+00 8.400
- 0.0000E+00 0.0000E+00 0.0000E+00
- 0.0000E+00 20.80 0.0000E+00
- 20.80 0.0000E+00 0.0000E+00
- d times e =
- 0.8320E-08 0.0000E+00 0.0000E+00
- 0.0000E+00 0.8320E-08 0.0000E+00
- 0.0000E+00 0.0000E+00 0.2820E-08
- Enter the unclamped dielectric constant K11
- [ 1300.0000 ]
- Enter the unclamped dielectric constant K33
- [ 1000.0000 ]
- Unclamped electric permitivity tensor=
- 0.1151E-07 0.0000E+00 0.0000E+00
- 0.0000E+00 0.1151E-07 0.0000E+00
- 0.0000E+00 0.0000E+00 0.8850E-08
- Clamped electric permitivity tensor=
- 0.3185E-08 0.0000E+00 0.0000E+00
- 0.0000E+00 0.3185E-08 0.0000E+00
- 0.0000E+00 0.0000E+00 0.6030E-08
- Enter density Kg/m^3 [7500]
- /COM
- /COM Material properties
- /COM Young’s Moduli
- EX, 2, 0.78561263E+11
- EY, 2, 0.78561263E+11
- EZ, 2, 0.62497537E+11
- 33/COM ANSYS "Major" Poisson ratios
- PRXY, 2, 0.28788955
- PRXZ, 2, 0.45203533
- PRYZ, 2, 0.45203533
- /COM Density Kg/m^3
- /COM DENS, 2, 0.75000000E-02
- /COM clamped Permitivities
- MP,PERX, 2, 0.31850000E-08
- MP,PERY, 2, 0.31850000E-08
- MP,PERZ, 2, 0.60300000E-08
- /COM ANSYS Piezoelectric "e" matrix
- TB,PIEZ,3
- TBDATA, 3, -5.7000000
- TBDATA, 6, -5.7000000
- TBDATA, 9, 8.4000000
- TBDATA, 14, 20.800000
- TBDATA, 16, 20.800000
- 0.20 Example, Orthotropic Elastic Constants
- Reference: Jim Emery "Piezoelectricity", (piezoelc.ps)
- Document location:/u51195/ps/piezoelc.ps,piezoelc.tex
- Anonymous FTP: ftp.os.kcp.com /pub/emery/
- Units are metric: Newton, Meter, Kilogram
- stress: Newton/M^2 (Pascals)
- Young’s Modulus: Pascals
- Elasticity coefficients: Pascals, and so on)
- Enter piezoelectric d constants (coulomb/newton)
- The IRE convention for piezoelectric labeling is used
- Type <return> for default value
- Enter d33 [ 2.0000000000000001E-10]
- Enter d31 [ -1.0000000000000000E-10]
- Enter d15 [ 4.0000000000000001E-10]
- d matrix=
- 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.4000E-09 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.4000E-09 0.0000E+00 0.0000E+00
- -0.1000E-09 -0.1000E-09 0.2000E-09 0.0000E+00 0.0000E+00 0.0000E+00
- Do you want to see the nonzero components
- of the 27 d tensor components? [n]
- Define the elasticity matrix or compliance matrix:
- (1)Use elastic constants to define compliance
- for orthotropic material, using Young’s moduli,
- Poissons ratios, and Shear Moduli.
- (2)Use the five components of the elastic matrix
- c11,c33,c44 (c44 is ANSYS c66),c12,c13,
- for a z-poled ceramic.
- (Note: c22=c11, c55=c44, c66=2(c11-c12),c23=c13,
- and c_{23}=c_{13}. Coefficients which are
- not in the upper 3-dimensional submatrix,
- not on the main diagonal, are zero.
- 34(3)Use the five components of the compliance matrix
- s11,s33,s44 (s44 is ANSYS s66),s12,s13,
- for a z-poled ceramic.
- (Note: s22=s11, s55=s44, s66=2(s11-s12),s23=s13,
- and s_{23}=s_{13}. Coefficients which are
- not in the upper 3-dimensional submatrix,
- not on the main diagonal, are zero.
- type <return> for default selection: [1]
- Enter the orthotropic elastic constants
- for a coordinate system in the principle directions
- Enter Young’s Modulus, in x [ 0.12800E+12]
- Enter Young’s Modulus, in y [ 0.12800E+12]
- Enter Young’s Modulus, in z [ 0.11000E+12]
- Enter ANSYS Poisson ratios (Theory sec. 2.1)
- Enter Major Poisson ratio prxy[ 0.30000 ]
- Enter Major Poisson ratio prxz[ 0.41976 ]
- Enter Major Poisson ratio pryz[ 0.41976 ]
- Enter shear modulus g23 [ 0.52000E+11]
- Enter shear modulus g13 [ 0.52000E+11]
- Enter shear modulus g12 [ 0.12200E+12]
- Compliance matrix (elasticity inverse) cinv=
- 0.7813E-11 -0.2344E-11 -0.3279E-11 0.0000E+00 0.0000E+00 0.0000E+00
- -0.2344E-11 0.7813E-11 -0.3279E-11 0.0000E+00 0.0000E+00 0.0000E+00
- -0.3279E-11 -0.3279E-11 0.9091E-11 0.0000E+00 0.0000E+00 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.1923E-10 0.0000E+00 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.1923E-10 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.8197E-11
- Note: In ANSYS components 4,5,6 are permuted
- (A different mapping from tensor to vector is used):
- ANSYS 44 is 66
- ANSYS 55 is 44
- ANSYS 66 is 55
- The five independent compliance coeficients are:
- s11= 0.78125000E-11
- s33= 0.90909091E-11
- s44= 0.19230769E-10
- s12=-0.23437500E-11
- s13=-0.32793388E-11
- Computing inverse matrix
- Elasticity matrix =
- 0.2104E+12 0.1119E+12 0.1163E+12 0.0000E+00 0.0000E+00 0.0000E+00
- 0.1119E+12 0.2104E+12 0.1163E+12 0.0000E+00 0.0000E+00 0.0000E+00
- 0.1163E+12 0.1163E+12 0.1939E+12 0.0000E+00 0.0000E+00 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.5200E+11 0.0000E+00 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.5200E+11 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.1220E+12
- Orthotropic constants from compliance matrix:
- Young’s Modulus 1= 0.12800000E+12
- Young’s Modulus 2= 0.12800000E+12
- Young’s Modulus 3= 0.11000000E+12
- Major Poisson ratio prxy= 0.30000000
- Major Poisson ratio prxz= 0.41975537
- Major Poisson ratio pryz= 0.41975537
- Shear Modulus g23= 0.52000000E+11
- 35Shear Modulus g13= 0.52000000E+11
- Shear Modulus g12= 0.12200000E+12
- Do you want to see the nonzero components
- of the 81 elasticity tensor components of c? [n]
- piezoelectric (stress) tensor coefficients
- Do you want to see the nonzero components
- of the 27 piezoelectric tensor components of e? [n]
- Piezoelectric e matrix=
- 0.0000E+00 0.0000E+00 -8.977
- 0.0000E+00 0.0000E+00 -8.977
- 0.0000E+00 0.0000E+00 15.52
- 0.0000E+00 20.80 0.0000E+00
- 20.80 0.0000E+00 0.0000E+00
- 0.0000E+00 0.0000E+00 0.0000E+00
- Second calculation:
- e13= -8.977066554171117
- e33= 15.52345455897376
- e42= 20.80000000000000
- Note: ANSYS e rows are permuted
- ANSYS row 4 is row 6
- ANSYS row 5 is row 4
- ANSYS row 6 is row 5
- ANSYS Piezoelectric e matrix=
- 0.0000E+00 0.0000E+00 -8.977
- 0.0000E+00 0.0000E+00 -8.977
- 0.0000E+00 0.0000E+00 15.52
- 0.0000E+00 0.0000E+00 0.0000E+00
- 0.0000E+00 20.80 0.0000E+00
- 20.80 0.0000E+00 0.0000E+00
- d times e =
- 0.8320E-08 0.0000E+00 0.0000E+00
- 0.0000E+00 0.8320E-08 0.0000E+00
- 0.0000E+00 0.0000E+00 0.4900E-08
- Enter the unclamped dielectric constant K11
- [ 1300.0000 ]
- Enter the unclamped dielectric constant K33
- [ 1000.0000 ]
- Unclamped electric permittivity tensor=
- 0.1151E-07 0.0000E+00 0.0000E+00
- 0.0000E+00 0.1151E-07 0.0000E+00
- 0.0000E+00 0.0000E+00 0.8850E-08
- Clamped electric permittivity tensor=
- 0.3185E-08 0.0000E+00 0.0000E+00
- 0.0000E+00 0.3185E-08 0.0000E+00
- 0.0000E+00 0.0000E+00 0.3950E-08
- Enter density Kg/m^3 [7500]
- /COM
- /COM Material properties
- /COM Young’s Moduli
- EX, 2, 0.12800000E+12
- EY, 2, 0.12800000E+12
- EZ, 2, 0.11000000E+12
- /COM ANSYS "Major" Poisson ratios
- PRXY, 2, 0.30000000
- 36PRXZ, 2, 0.41975537
- PRYZ, 2, 0.41975537
- /COM Density Kg/m^3
- /COM DENS, 2, 0.75000000E-02
- /COM clamped Permitivities
- MP,PERX, 2, 0.31850000E-08
- MP,PERY, 2, 0.31850000E-08
- MP,PERZ, 2, 0.39498958E-08
- /COM ANSYS Piezoelectric "e" matrix
- TB,PIEZ,3
- TBDATA, 3, -8.9770666
- TBDATA, 6, -8.9770666
- TBDATA, 9, 15.523455
- TBDATA, 14, 20.800000
- TBDATA, 16, 20.800000
- 0.21 Program Listing of pzansys.ftn Program
- Here is a listing of the program. The program works through tensor summations, matrix calculations, and matrix inversions. Each subroutine has a one
- line description and a description of the parameters.
- % cat pzansys.ftn
- c pzansys.ftn stress and strain versions of the piezoelectric tensor
- c Version 2/6/97
- c Author: Jim Emery (AlliedSignal Kansas City)
- c for the ansys finite element program.
- column 11111111112222222222333333333344444444445555555555666666666677777777778
- c2345678901234567890123456789012345678901234567890123456789012345678901234567890
- c Reference: Jim Emery "Piezoelectricity" (File: piezoelc.tex)
- implicit real*8 (a-h,o-z)
- dimension d(3,3,3)
- dimension e(3,3,3)
- dimension c(3,3,3,3)
- dimension dc(3,3)
- dimension cmat(6,6)
- dimension cmatinv(6,6)
- dimension a(6,6),b(6,6),cc(6,6)
- dimension dmat(3,6)
- dimension emat(6,3)
- dimension epsilon(3,3)
- dimension clamped(3,3)
- dimension ain(10)
- dimension pr(3)
- dimension ym(3)
- real*8 nu12,nu23,nu13,nu21,nu32,nu31
- character*1 cm
- character*1 reply
- character*53 cs1
- zero=0.
- c piezoelectric constants (coulomb/newton)
- 37do i=1,3
- do j=1,6
- dmat(i,j)=0.
- enddo
- enddo
- dmat(3,3)=200e-12
- dmat(3,1)=-100e-12
- dmat(1,5)=400e-12
- write(*,*)’Reference: Jim Emery "Piezoelectricity", (piezoelc.ps)’
- write(*,*)’Document location:/u51195/ps/piezoelc.ps,piezoelc.tex ’
- write(*,*)’Anonymous FTP: ftp.os.kcp.com /pub/emery/ ’
- write(*,*)’Units are metric: Newton, Meter, Kilogram’
- write(*,*)’stress: Newton/M^2 (Pascals)’
- write(*,*)’Young’’s Modulus: Pascals’
- write(*,*)’Elasticity coefficients: Pascals, and so on)’
- write(*,*)’Enter piezoelectric d constants (coulomb/newton)’
- write(*,*)’The IRE convention for piezoelectric labeling is used’
- write(*,*)’Type <return> for default value’
- write(*,*)’Enter d33 [’,dmat(3,3),’]’
- call readr(0,ain,nr)
- if(nr .ge. 1)then
- dmat(3,3)=ain(1)
- endif
- write(*,*)’Enter d31 [’,dmat(3,1),’]’
- call readr(0,ain,nr)
- if(nr .ge. 1)then
- dmat(3,1)=ain(1)
- endif
- dmat(3,2)=dmat(3,1)
- write(*,*)’Enter d15 [’,dmat(1,5),’]’
- call readr(0,ain,nr)
- if(nr .ge. 1)then
- dmat(1,5)=ain(1)
- endif
- dmat(2,4)=dmat(1,5)
- write(*,*)’ d matrix= ’
- do i=1,3
- write(*,’(6(g11.4,1x))’)(dmat(i,j),j=1,6)
- enddo
- c construct the components of the d tensor
- do i=1,3
- do j=1,3
- do k=1,3
- call t2vec(j,k,jk)
- if(j .eq. k)then
- d(i,j,k)=dmat(i,jk)
- else
- d(i,j,k)=dmat(i,jk)/2.
- endif
- enddo
- enddo
- enddo
- write(*,*)’Do you want to see the nonzero components’
- write(*,*)’of the 27 d tensor components? [n]’
- read(*,’(a)’)reply
- 38if(lenstr(reply) .eq. 0)then
- reply=’n’
- endif
- if(reply .eq. ’y’)then
- do i=1,3
- do j=1,3
- do k=1,3
- if(d(i,j,k) .ne. zero)then
- write(*,’(a,i1,i1,i1,a,g15.8)’)’d(’,i,j,k,’)=’,d(i,j,k)
- endif
- enddo
- enddo
- enddo
- endif
- c orthotropic elastic constants
- write(*,*)’Define the elasticity matrix or compliance matrix:’
- write(*,*)
- write(*,*)’(1)Use elastic constants to define compliance’
- write(*,*)’for orthotropic material, using Young’’s moduli,’
- write(*,*)’Poissons ratios, and Shear Moduli.’
- write(*,*)
- write(*,*)’(2)Use the five components of the elastic matrix’
- write(*,*)’c11,c33,c44 (c44 is ANSYS c66),c12,c13, ’
- write(*,*)’for a z-poled ceramic.’
- write(*,*)’(Note: c22=c11, c55=c44, c66=2(c11-c12),c23=c13,’
- write(*,*)’and c_{23}=c_{13}. Coefficients which are’
- write(*,*)’not in the upper 3-dimensional submatrix,’
- write(*,*)’not on the main diagonal, are zero.’
- write(*,*)
- write(*,*)’(3)Use the five components of the compliance matrix’
- write(*,*)’s11,s33,s44 (s44 is ANSYS s66),s12,s13,’
- write(*,*)’for a z-poled ceramic.’
- write(*,*)’(Note: s22=s11, s55=s44, s66=2(s11-s12),s23=s13,’
- write(*,*)’and s_{23}=s_{13}. Coefficients which are’
- write(*,*)’not in the upper 3-dimensional submatrix,’
- write(*,*)’not on the main diagonal, are zero.’
- write(*,*)’type <return> for default selection: [1]’
- read(*,’(a)’)reply
- if(lenstr(reply) .eq. 0)then
- reply=’1’
- endif
- c2345678901234567890123456789012345678901234567890123456789012345678901234567890
- c begin case1
- if(reply .eq. ’1’)then
- write(*,*)’Enter the orthotropic elastic constants’
- write(*,*)’for a coordinate system in the principle directions’
- e1=12.8e10
- write(*,’(a,g12.5,a)’)’Enter Young’’s Modulus, in x [’,e1,’]’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- 39e1=ain(1)
- endif
- e2=12.8e10
- write(*,’(a,g12.5,a)’)’Enter Young’’s Modulus, in y [’,e2,’]’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- e2=ain(1)
- endif
- e3=11.0e10
- write(*,’(a,g12.5,a)’)’Enter Young’’s Modulus, in z [’,e3,’]’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- e3=ain(1)
- endif
- c write(*,’(a)’)’NOTE. The poisson ratio nuij is the ’
- c write(*,’(a)’)’the strain ratio -epsilon_j/epsilon_i ’
- c write(*,’(a)’)’under a normal stress sigma_i’
- write(*,*)
- c nu31=.31
- write(*,*)’Enter ANSYS Poisson ratios (Theory sec. 2.1)’
- prxy=.3
- prxz=.41975537
- pryz=.41975537
- write(*,’(a,g12.5,a)’)’Enter Major Poisson ratio prxy[’,prxy,’]’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- prxy=ain(1)
- endif
- write(*,’(a,g12.5,a)’)’Enter Major Poisson ratio prxz[’,prxz,’]’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- prxz=ain(1)
- endif
- write(*,’(a,g12.5,a)’)’Enter Major Poisson ratio pryz[’,pryz,’]’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- prxz=ain(1)
- endif
- c g23=(e1*e2)/(e1+e2+2.*nu12*e1)
- g23=5.2e10
- write(*,’(a,g12.5,a)’)’Enter shear modulus g23 [’,g23,’]’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- g23=ain(1)
- endif
- c g13=(e1*e2)/(e1+e2+2.*nu12*e1)
- 40g13=5.2e10
- write(*,’(a,g12.5,a)’)’Enter shear modulus g13 [’,g13,’]’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- g13=ain(1)
- endif
- c g12=(e1*e2)/(e1+e2+2.*nu12*e1)
- g12=12.2e10
- write(*,’(a,g12.5,a)’)’Enter shear modulus g12 [’,g12,’]’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- g12=ain(1)
- endif
- c build the compliance matrix
- do i=1,6
- do j=1,6
- cmatinv(i,j)=0.
- enddo
- enddo
- cmatinv(1,1)=1./e1
- cmatinv(2,2)=1./e2
- cmatinv(3,3)=1./e3
- cmatinv(1,2)=-prxy/e1
- cmatinv(2,1)=cmatinv(1,2)
- cmatinv(1,3)=-prxz/e1
- cmatinv(3,1)=cmatinv(1,3)
- cmatinv(2,3)=-pryz/e2
- cmatinv(3,2)=cmatinv(2,3)
- cmatinv(4,4)=1/g23
- cmatinv(5,5)=1/g13
- cmatinv(6,6)=1/g12
- write(*,*)’Compliance matrix (elasticity inverse) cinv= ’
- do i=1,6
- write(*,’(6(g11.4,1x))’)(cmatinv(i,j),j=1,6)
- enddo
- write(*,*)’Note: In ANSYS components 4,5,6 are permuted’
- write(*,*)’(A different mapping from tensor to vector is used):’
- write(*,*)’ANSYS 44 is 66’
- write(*,*)’ANSYS 55 is 44’
- write(*,*)’ANSYS 66 is 55’
- write(*,*)’The five independent compliance coeficients are:’
- write(*,’(a,g15.8)’)’s11=’,cmatinv(1,1)
- write(*,’(a,g15.8)’)’s33=’,cmatinv(3,3)
- write(*,’(a,g15.8)’)’s44=’,cmatinv(4,4)
- write(*,’(a,g15.8)’)’s12=’,cmatinv(1,2)
- write(*,’(a,g15.8)’)’s13=’,cmatinv(1,3)
- do i=1,6
- do j=1,6
- a(i,j)=cmatinv(i,j)
- enddo
- 41enddo
- ia=6
- ib=6
- n=6
- m=6
- inv=1
- eps=1.e-10
- idet=0
- write(*,*)’Computing inverse matrix’
- call gaussr(a,ia,b,ib,n,m,inv,eps,idet,det,ier)
- if(ier .ne. 0)then
- write(*,*)’ matrix is singular ’
- endif
- do i=1,6
- do j=1,6
- cmat(i,j)=b(i,j)
- enddo
- enddo
- write(*,*)’ Elasticity matrix = ’
- do i=1,6
- write(*,’(6(g11.4,1x))’)(cmat(i,j),j=1,6)
- enddo
- m=6
- n=6
- l=6
- ic=6
- call matm(cmatinv,ia,m,n,b,ib,l,cc,ic)
- c write(*,*)’Compliance matrix times elasticity matrix= ’
- c do i=1,6
- c write(*,’(6(g11.4,1x))’)(cc(i,j),j=1,6)
- c enddo
- endif
- c end of case1
- c begin case2
- if(reply .eq. ’2’)then
- do i=1,6
- do j=1,6
- cmat(i,j)=0.
- enddo
- enddo
- cmat(1,1)=13.2e10
- write(*,’(a,g12.5,a)’)’Enter c11 [’,cmat(1,1),’]’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- cmat(1,1)=ain(1)
- endif
- cmat(2,2)=cmat(1,1)
- cmat(3,3)=11.5e10
- write(*,’(a,g12.5,a)’)’Enter c33 [’,cmat(3,3),’]’
- 42call readr(0,ain,nr)
- if(nr .eq. 1)then
- cmat(3,3)=ain(1)
- endif
- cmat(4,4)=5.2e10
- write(*,’(a,g12.5,a)’)’Enter c44 (ANSYS c66) [’,cmat(4,4),’]’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- cmat(4,4)=ain(1)
- endif
- cmat(5,5)=cmat(4,4)
- cmat(1,2)=7.1e10
- write(*,’(a,g12.5,a)’)’Enter c12 [’,cmat(1,2),’]’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- cmat(1,2)=ain(1)
- endif
- cmat(2,1)=cmat(1,2)
- cmat(1,3)=7.3e10
- write(*,’(a,g12.5,a)’)’Enter c13 [’,cmat(1,3),’]’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- cmat(1,3)=ain(1)
- endif
- cmat(3,1)=cmat(1,3)
- cmat(2,3)=cmat(1,3)
- cmat(3,2)=cmat(2,3)
- cmat(6,6)=2.*(cmat(1,1)-cmat(1,2))
- write(*,*)’Elasticity matrix c=’
- do i=1,6
- write(*,’(6(g11.4,1x))’)(cmat(i,j),j=1,6)
- enddo
- write(*,*)’Note: In ANSYS components 4,5,6 are permuted’
- write(*,*)’ANSYS 44 is 66’
- write(*,*)’ANSYS 55 is 44’
- write(*,*)’ANSYS 66 is 55’
- do i=1,6
- do j=1,6
- a(i,j)=cmat(i,j)
- enddo
- enddo
- ia=6
- ib=6
- n=6
- m=6
- inv=1
- eps=1.e-10
- idet=0
- 43call gaussr(a,ia,b,ib,n,m,inv,eps,idet,det,ier)
- if(ier .ne. 0)then
- write(*,*)’ matrix is singular ’
- endif
- do i=1,6
- do j=1,6
- cmatinv(i,j)=b(i,j)
- enddo
- enddo
- write(*,*)’Compliance matrix= ’
- do i=1,6
- write(*,’(6(g11.4,1x))’)(cmatinv(i,j),j=1,6)
- enddo
- m=6
- n=6
- l=6
- ic=6
- call matm(cmat,ia,m,n,cmatinv,ib,l,cc,ic)
- c write(*,*)’Compliance matrix times elasticity matrix= ’
- c do i=1,6
- c write(*,’(6(g11.4,1x))’)(cc(i,j),j=1,6)
- c enddo
- endif
- c end case2
- c begin case3
- if(reply .eq. ’3’)then
- do i=1,6
- do j=1,6
- cmatinv(i,j)=0.
- enddo
- enddo
- cmatinv(1,1) = 1.65e-11
- cmatinv(3,3) = 2.07e-11
- cmatinv(4,4) = 4.35e-11
- cmatinv(1,2) = -4.78e-12
- cmatinv(1,3) = -8.45e-12
- write(*,’(a,g12.5,a)’)’Enter s11 [’,cmatinv(1,1),’]’
- write(*,*)’Reference for default values:’
- write(*,*)’Auld, Appendix A.4, PZT-5H’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- cmatinv(1,1)=ain(1)
- endif
- cmatinv(2,2)=cmatinv(1,1)
- 44write(*,’(a,g12.5,a)’)’Enter s33 [’,cmatinv(3,3),’]’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- cmatinv(3,3)=ain(1)
- endif
- write(*,’(a,g12.5,a)’)’Enter s44 (ANSYS c66) [’,cmatinv(4,4),’]’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- cmatinv(4,4)=ain(1)
- endif
- cmatinv(5,5)=cmatinv(4,4)
- write(*,’(a,g12.5,a)’)’Enter s12 [’,cmatinv(1,2),’]’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- cmatinv(1,2)=ain(1)
- endif
- cmatinv(2,1)=cmatinv(1,2)
- write(*,’(a,g12.5,a)’)’Enter s13 [’,cmatinv(1,3),’]’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- cmatinv(1,3)=ain(1)
- endif
- cmatinv(3,1)=cmatinv(1,3)
- cmatinv(2,3)=cmatinv(1,3)
- cmatinv(3,2)=cmatinv(2,3)
- cmatinv(6,6)=2.*(cmatinv(1,1)-cmatinv(1,2))
- write(*,*)’Compliance matrix s= cinv =’
- do i=1,6
- write(*,’(6(g11.4,1x))’)(cmatinv(i,j),j=1,6)
- enddo
- write(*,*)’Note: In ANSYS components 4,5,6 are permuted’
- write(*,*)’ANSYS 44 is 66’
- write(*,*)’ANSYS 55 is 44’
- write(*,*)’ANSYS 66 is 55’
- do i=1,6
- do j=1,6
- a(i,j)=cmatinv(i,j)
- enddo
- enddo
- ia=6
- ib=6
- n=6
- m=6
- inv=1
- eps=1.e-10
- idet=0
- write(*,*)’Computing inverse matrix’
- call gaussr(a,ia,b,ib,n,m,inv,eps,idet,det,ier)
- if(ier .ne. 0)then
- write(*,*)’ matrix is singular ’
- 45endif
- do i=1,6
- do j=1,6
- cmat(i,j)=b(i,j)
- enddo
- enddo
- write(*,*)’ Elasticity matrix = ’
- do i=1,6
- write(*,’(6(g11.4,1x))’)(cmat(i,j),j=1,6)
- enddo
- m=6
- n=6
- l=6
- ic=6
- call matm(cmatinv,ia,m,n,b,ib,l,cc,ic)
- c write(*,*)’Compliance matrix times elasticity matrix= ’
- c do i=1,6
- c write(*,’(6(g11.4,1x))’)(cc(i,j),j=1,6)
- c enddo
- endif
- c end case3
- write(*,*)’Orthotropic constants from compliance matrix:’
- e1=1./cmatinv(1,1)
- e2=1./cmatinv(2,2)
- e3=1./cmatinv(3,3)
- write(*,’(a,g15.8)’)’Young’’s Modulus 1= ’,e1
- write(*,’(a,g15.8)’)’Young’’s Modulus 2= ’,e2
- write(*,’(a,g15.8)’)’Young’’s Modulus 3= ’,e3
- prxy=-cmatinv(1,2)*e1
- write(*,’(a,g15.8)’)’Major Poisson ratio prxy=’,prxy
- prxz=-cmatinv(1,3)*e1
- write(*,’(a,g15.8)’)’Major Poisson ratio prxz=’,prxz
- pryz=-cmatinv(2,3)*e2
- write(*,’(a,g15.8)’)’Major Poisson ratio pryz=’,pryz
- g23= 1./cmatinv(4,4)
- g13= 1./cmatinv(5,5)
- g12= 1./cmatinv(6,6)
- write(*,’(a,g15.8)’)’Shear Modulus g23= ’,g23
- write(*,’(a,g15.8)’)’Shear Modulus g13= ’,g13
- write(*,’(a,g15.8)’)’Shear Modulus g12= ’,g12
- write(*,*)
- c orthotropic elasticity tensor
- do i=1,3
- do j=1,3
- do k=1,3
- e(i,j,k)=0.
- do l=1,3
- c(i,j,k,l)=0.
- enddo
- enddo
- enddo
- 46enddo
- do i=1,3
- do j=1,3
- call t2vec(i,j,ij)
- do k=1,3
- do l=1,3
- call t2vec(k,l,kl)
- if(k .eq. l)then
- c(i,j,k,l)=cmat(ij,kl)
- else
- c(i,j,k,l)=cmat(ij,kl)/2.
- endif
- enddo
- enddo
- enddo
- enddo
- c
- write(*,*)’Do you want to see the nonzero components’
- write(*,*)’of the 81 elasticity tensor components of c? [n]’
- read(*,’(a)’)reply
- if(lenstr(reply) .eq. 0)then
- reply=’n’
- endif
- if(reply .eq. ’y’)then
- do i=1,3
- do j=1,3
- do k=1,3
- do l=1,3
- if(c(i,j,k,l) .ne. zero)then
- write(*,’(a,i1,i1,i1,i1,a,g15.8)’)’c(’,i,j,k,l,’)=’,c(i,j,k,l)
- endif
- enddo
- enddo
- enddo
- enddo
- endif
- write(*,*)’ piezoelectric (stress) tensor coefficients’
- do i=1,3
- do j=1,3
- do k=1,3
- e(i,j,k)=0.
- do l=1,3
- do m=1,3
- e(i,j,k) = e(i,j,k) + d(i,l,m)*c(l,m,j,k)
- enddo
- enddo
- c write(*,’(a,i1,i1,i1,a,g15.8)’)’e(’,i,j,k,’)=’,e(i,j,k)
- enddo
- enddo
- enddo
- write(*,*)’Do you want to see the nonzero components’
- write(*,*)’of the 27 piezoelectric tensor components of e? [n]’
- read(*,’(a)’)reply
- if(lenstr(reply) .eq. 0)then
- reply=’n’
- 47endif
- if(reply .eq. ’y’)then
- do i=1,3
- do j=1,3
- do k=1,3
- if(e(i,j,k) .ne. zero)then
- write(*,’(a,i1,i1,i1,a,g15.8)’)’e(’,i,j,k,’)=’,e(i,j,k)
- endif
- enddo
- enddo
- enddo
- endif
- c compute the e piezoelectric matrix
- do i=1,3
- do jk=1,6
- call vec2t(jk,j,k)
- if(j .eq. k)then
- emat(jk,i) = e(i,j,k)
- else
- emat(jk,i) = 2.*e(i,j,k)
- endif
- enddo
- enddo
- c
- write(*,*)’Piezoelectric e matrix= ’
- do i=1,6
- write(*,’(3(g11.4,1x))’)(emat(i,j),j=1,3)
- enddo
- write(*,*)’Second calculation:’
- e13=cmat(1,1)*dmat(3,1)+cmat(1,2)*dmat(3,1)+cmat(1,3)*dmat(3,3)
- write(*,*)’e13=’,e13
- e33=cmat(1,3)*dmat(3,1)+cmat(1,3)*dmat(3,1)+cmat(3,3)*dmat(3,3)
- write(*,*)’e33=’,e33
- e42=cmat(4,4)*dmat(1,5)
- write(*,*)’e42=’,e42
- write(*,*)’Note: ANSYS e rows are permuted’
- write(*,*)’ANSYS row 4 is row 6 ’
- write(*,*)’ANSYS row 5 is row 4 ’
- write(*,*)’ANSYS row 6 is row 5 ’
- write(*,*)’ANSYS Piezoelectric e matrix= ’
- do i=1,3
- write(*,’(3(g11.4,1x))’)(emat(i,j),j=1,3)
- enddo
- write(*,’(3(g11.4,1x))’)(emat(6,j),j=1,3)
- write(*,’(3(g11.4,1x))’)(emat(4,j),j=1,3)
- write(*,’(3(g11.4,1x))’)(emat(5,j),j=1,3)
- c dielectric constants (farads/meter)
- 48c dc(1,1)=7.12e-9
- c dc(2,2)=7.12e-9
- c dc(3,3)=5.84e-9
- c density (kilograms/meter^3)
- c density=7.5e3
- cm=’,’
- idmat=3
- m=3
- n=6
- iemat=6
- l=3
- icc=6
- call matm(dmat,idmat,m,n,emat,iemat,l,cc,icc)
- write(*,*)’d times e = ’
- do i=1,3
- write(*,’(3(g11.4,1x))’)(cc(i,j),j=1,3)
- enddo
- c compute permittivity tensor
- eps0=8.85e-12
- do i=1,3
- do j=1,3
- epsilon(i,j)=0.
- enddo
- enddo
- dielx=1300.
- write(*,’(a)’)’Enter the unclamped dielectric constant K11’
- write(*,’(a,g15.8,a)’)’[’,dielx,’]’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- dielx=ain(1)
- endif
- epsilon(1,1)=dielx*eps0
- diely=dielx
- c cs1=’Enter the dielectric constant K22’
- c write(*,’(a,a,g15.8,a)’)cs1,’ [’,diely,’]’
- c call readr(0,ain,nr)
- c if(nr .eq. 1)then
- c diely=ain(1)
- c endif
- epsilon(2,2)=diely*eps0
- dielz=1000.
- write(*,’(a)’)’Enter the unclamped dielectric constant K33’
- write(*,’(a,g15.8,a)’)’[’,dielz,’]’
- call readr(0,ain,nr)
- if(nr .eq. 1)then
- dielz=ain(1)
- endif
- epsilon(3,3)=dielz*eps0
- write(*,*)’Unclamped electric permittivity tensor=’
- do i=1,3
- 49write(*,’(3(g11.4,1x))’)(epsilon(i,j),j=1,3)
- enddo
- do i=1,3
- do j=1,3
- clamped(i,j)= epsilon(i,j) - cc(i,j)
- enddo
- enddo
- write(*,*)’Clamped electric permittivity tensor=’
- do i=1,3
- write(*,’(3(g11.4,1x))’)(clamped(i,j),j=1,3)
- enddo
- do i=1,3
- do j=1,3
- sum=0.
- do k=1,3
- do l=1,3
- sum=sum+d(i,k,l)*e(j,k,l)
- c if((i .eq. 1) .and. (j .eq. 1))then
- c write(*,*)k,l,’ d= ’,d(i,k,l),’ e= ’,e(j,k,l)
- c endif
- enddo
- enddo
- epsilon(i,j)=epsilon(i,j)-sum
- enddo
- enddo
- c write(*,*)’Clamped electric permittivity tensor=’
- c do i=1,3
- c write(*,’(3(g11.4,1x))’)(epsilon(i,j),j=1,3)
- c enddo
- rho= 7.500000E-03
- write(*,*)’Enter density Kg/m^3 [7500]’
- call readr(0,ain,nr)
- if(nr .ge. 1)then
- rho=ain(1)
- endif
- write(*,’(a)’)’/COM ’
- write(*,’(a)’)’/COM Material properties’
- c material number
- mn=2
- write(*,’(a)’)’/COM Young’’s Moduli’
- write(*,’(a,i3,a,g15.8)’)’EX,’,mn,cm,e1
- write(*,’(a,i3,a,g15.8)’)’EY,’,mn,cm,e2
- write(*,’(a,i3,a,g15.8)’)’EZ,’,mn,cm,e3
- write(*,’(a)’)’/COM ANSYS "Major" Poisson ratios’
- c reference ANSYS Theory 2.1 structural fundamentals
- prxy=-cmatinv(1,2)*e1
- write(*,’(a,i3,a,g15.8)’)’PRXY,’,mn,cm,prxy
- 50prxz=-cmatinv(1,3)*e1
- write(*,’(a,i3,a,g15.8)’)’PRXZ,’,mn,cm,prxz
- pryz=-cmatinv(2,3)*e2
- write(*,’(a,i3,a,g15.8)’)’PRYZ,’,mn,cm,pryz
- write(*,’(a)’)’/COM Density Kg/m^3’
- write(*,’(a,i3,a,g15.8)’)’/COM DENS,’,mn,cm,rho
- write(*,’(a)’)’/COM clamped Permitivities’
- c epsilon(1,1)=8.7969e-12
- c epsilon(2,2)=8.7969e-12
- c epsilon(3,3)=8.7969e-12
- write(*,’(a,i3,a,g15.8)’)’MP,PERX,’,mn,cm,clamped(1,1)
- write(*,’(a,i3,a,g15.8)’)’MP,PERY,’,mn,cm,clamped(2,2)
- write(*,’(a,i3,a,g15.8)’)’MP,PERZ,’,mn,cm,clamped(3,3)
- write(*,’(a)’)’/COM ANSYS Piezoelectric "e" matrix’
- write(*,’(a)’)’TB,PIEZ,3’
- write(*,’(a,i3,a,g15.8)’)’TBDATA,’,3,cm,emat(1,3)
- write(*,’(a,i3,a,g15.8)’)’TBDATA,’,6,cm,emat(2,3)
- write(*,’(a,i3,a,g15.8)’)’TBDATA,’,9,cm,emat(3,3)
- c ansysemat(5,2)=emat(4,2)
- write(*,’(a,i3,a,g15.8)’)’TBDATA,’,14,cm,emat(4,2)
- c ansysemat(6,1)=emat(5,1)
- write(*,’(a,i3,a,g15.8)’)’TBDATA,’,16,cm,emat(5,1)
- end
- c+ readr read a row of floating point numbers
- subroutine readr(nf, a, nr)
- implicit real*8(a-h,o-z)
- c numbers are separated by spaces
- c examples of valid numbers are:
- c 12.13 34 45e4 4.78e-6 4e2,5.6D-23,10000.d015
- c nf=file number, 0 for standard input file
- c a=array of returned numbers
- c nr=number of values in returned array,
- c or 0 for empty or blank line,
- c or -1 for end of file on unit nf.
- c requires functions val and length
- dimension a(*)
- character*200 b
- character*200 c
- character*1 d
- c=’ ’
- if(nf.eq.0)then
- read(*,’(a)’,end=99)b
- else
- read(nf,’(a)’,end=99)b
- endif
- nr=0
- l=lenstr(b)
- if(l.ge.200)then
- write(*,*)’ error in readr subroutine ’
- write(*,*)’ record is too long ’
- endif
- do 1 i=1,l
- d=b(i:i)
- if (d.ne.’ ’) then
- 51k=lenstr(c)
- if (k.gt.0)then
- c=c(1:k)//d
- else
- c=d
- endif
- endif
- if( (d.eq.’ ’).or.(i.eq.l)) then
- if (c.ne.’ ’) then
- nr=nr+1
- call valsub(c,a(nr),ier)
- c=’ ’
- endif
- endif
- 1 continue
- return
- 99 nr=-1
- return
- end
- c
- c+ lenstr nonblank length of string
- function lenstr(s)
- c length of the substring of s obtained by deleting all
- c trailing blanks from s. thus the length of a string
- c containing only blanks will be 0.
- character s*(*)
- lenstr=0
- n=len(s)
- do 10 i=n,1,-1
- if(s(i:i) .ne. ’ ’)then
- lenstr=i
- return
- endif
- 10 continue
- return
- end
- c+ valsub converts string to floating point number (r*8)
- subroutine valsub(s,v,ier)
- implicit real*8(a-h,o-z)
- c examples of valid strings are: 12.13 34 45e4 4.78e-6 4E2
- c the string is checked for valid characters,
- c but the string can still be invalid.
- c s-string
- c v-returned value
- c ier- 0 normal
- c 1 if invalid character found, v returned 0
- c
- logical p
- character s*(*),c*50,t*50,ch*15
- character z*1
- data ch/’1234567890+-.eE’/
- v=0.
- ier=1
- l=lenstr(s)
- if(l.eq.0)return
- 52p=.true.
- do 10 i=1,l
- z=s(i:i)
- if((z.eq.’D’).or.(z.eq.’d’))then
- s(i:i)=’e’
- endif
- p=p.and.(index(ch,s(i:i)).ne.0)
- 10 continue
- if(.not.p)return
- n=index(s,’.’)
- if(n.eq.0)then
- n=index(s,’e’)
- if(n.eq.0)n=index(s,’E’)
- if(n.eq.0)n=index(s,’d’)
- if(n.eq.0)n=index(s,’D’)
- if(n.eq.0)then
- s=s(1:l)//’.’
- else
- t=s(n:l)
- s=s(1:(n-1))//’.’//t
- endif
- l=l+1
- endif
- write(c,’(a30)’)s(1:l)
- read(c,’(g30.23)’)v
- ier=0
- return
- end
- c+ str floating point number to string
- subroutine str(x,s)
- implicit real*8(a-h,o-z)
- character s*25,c*25,b*25,e*25
- zero=0.
- if(x.eq.zero)then
- s=’0’
- return
- endif
- write(c,’(g11.4)’)x
- read(c,’(a25)’)b
- l=lenstr(b)
- do 10 i=1,l
- n1=i
- if(b(i:i).ne.’ ’)go to 20
- 10 continue
- 20 continue
- if(b(n1:n1).eq.’0’)n1=n1+1
- b=b(n1:l)
- l=l+1-n1
- k=index(b,’E’)
- if(k.gt.0)e=b(k:l)
- if(k.gt.0)then
- s=b(1:(k-1))
- k1=index(b,’E+0’)
- if(k1.gt.0)then
- e=’E’//b((k1+3):l)
- 53else
- k1=index(b,’E+’)
- if(k1.gt.0)e=’E’//b((k1+2):l)
- endif
- k1=index(b,’E-0’)
- if(k1.gt.0)e=’E-’//b((k1+3):l)
- l=k-1
- else
- s=b
- endif
- j=index(s,’.’)
- n2=l
- if(j.ne.0)then
- do 30 i=1,l
- n2=l+1-i
- if(s(n2:n2).ne.’0’)go to 40
- 30 continue
- endif
- 40 continue
- s=s(1:n2)
- if(s(n2:n2).eq.’.’)then
- s=s(1:(n2-1))
- n2=n2-1
- endif
- if(k.gt.0)s=s(1:n2)//e
- return
- end
- c+ t2vec stress tensor index to vector index
- subroutine t2vec(i,j,k)
- c input:
- c i,j
- c output:
- c k
- c so that sigma(k)=sigma(i,j)
- integer m(3,3)
- data m/1,6,5,6,2,4,5,4,3/
- k=m(i,j)
- return
- end
- c+ vec2t stress vector index to tensor index
- subroutine vec2t(k,i,j)
- c input:
- c k
- c output:
- c i,j
- c so that sigma(i,j)=sigma(k)
- integer mi(6),mj(6)
- data mi/1,2,3,2,1,1/
- data mj/1,2,3,3,3,2/
- i=mi(k)
- j=mj(k)
- return
- end
- c+ gaussr solution of linear equations, inverse, determinant (real) new version
- c gaussr2.ftn 4/17/96 modernization of gaussr under construction
- 54subroutine gaussr(a,ia,b,ib,n,m,inv,eps,idet,det,ier)
- c solves the equation a*c=b for c, where a is an n by n matrix
- c c and b are n row by m column matrices. c is returned as b.
- c algorithm -gaussian elimination with partial pivoting.
- c parameters a-n by n matrix containing the coefficients of
- c the linear system.
- c ia-row dimension of a in defining routine
- c e.g. in the routine where a is defined,
- c a might be dimensioned as:
- c dimension a(nr,nc)
- c then ia must be set to nr. we may have n < ia, but
- c must not have n > ia, or n*n > nr*nc.
- c ia is needed for proper addressing of matrix a.
- c fortran stores by column first: a(i,j)=a(i+(j-1)*ia))
- c b-n by m matrix containing the m right sides
- c of the equations, on entering. on returning, b
- c contains the solutions. the inverse of a is
- c returned in b when inv=1
- c ib-row dimension of b in defining routine
- c n-row and column dimension of a.
- c m-column dimension of b (usually 1)
- c the program changes m to n when inv=1
- c inv-the inverse of a is calculated
- c and returned in b when inv=1
- c b must be large enough to hold the inverse
- c eps-each equation is normalized so that the
- c coefficients are <= 1 in magnitude.
- c when a pivot is less than eps the matrix is
- c considered nearly singular, and ier is set to 1
- c if a pivot is zero the matrix is singular, and
- c ier is set to 2. one may set eps=1.e-5 for
- c single precision, and 1.e-12 for double.
- c eps does not effect any calculation.
- c normalization may also prevent exponent overflow.
- c idet-compute determinant only if idet = 1
- c determinants are products of n numbers.
- c overflow can occur if the elements of the
- c matrix have large exponents.
- c set idet=0 if the determinant is not needed.
- c det-determinant of a.
- c ier-return parameter,
- c ier=0 normal return
- c ier=1 matrix is nearly singular
- c ier=2 matrix is singular
- c
- c warning!! the subroutine changes a and b. if they need to be
- c saved, copies must be made before calling the subroutine.
- c the subroutine can be converted to different number type
- c by uncommenting the appropriate implicit statement.
- implicit real*8(a-h,o-z)
- c implicit complex(a-h,o-z)
- c implicit complex*16(a-h,o-z)
- logical cdet
- dimension a(ia,*),b(ib,*)
- cdet = idet .eq. 1
- 55zero=0.
- ier=0
- det=1.
- if(m.le.0)m=1
- if(inv.eq.1)then
- c set b equal to the identity
- do i=1,n
- do j=1,n
- b(i,j)=0.
- if(i.eq.j)b(i,j)=1.
- enddo
- enddo
- m=n
- endif
- c normalize rows
- do 20 i=1,n
- bigest=a(i,1)
- do 16 j=2,n
- ab=a(i,j)
- if(abs(ab).gt.abs(bigest))bigest=ab
- 16 continue
- if(bigest.eq.zero)then
- ier=2
- det=0.
- return
- endif
- if(cdet)det=det*bigest
- do 18 j=1,n
- a(i,j)=a(i,j)/bigest
- 18 continue
- do 19 j=1,m
- b(i,j)=b(i,j)/bigest
- 19 continue
- 20 continue
- j=1
- do while( j .lt. n)
- kk=j+1
- l=j
- c find row l with largest pivot
- do 32 i=kk,n
- if(abs(a(i,j)).gt.abs(a(l,j)))l=i
- 32 continue
- if(abs(a(l,j)).eq.zero)then
- ier=2
- det=0.
- return
- endif
- if(abs(a(l,j)).le.abs(eps))ier=1
- if(l.ne.j)then
- c interchange rows l and j
- do 37 k=1,n
- c=a(l,k)
- a(l,k)=a(j,k)
- a(j,k)=c
- 37 continue
- 56do 39 k=1,m
- c=b(l,k)
- b(l,k)=b(j,k)
- b(j,k)=c
- 39 continue
- if(cdet)det=det*(-1.)
- endif
- if(cdet)det=det*a(j,j)
- c divide row by pivot
- c=a(j,j)
- do 50 k=j,n
- a(j,k)=a(j,k)/c
- 50 continue
- do 55 k=1,m
- b(j,k)=b(j,k)/c
- 55 continue
- c add multiple of row j to lower rows
- c to eliminate jth coefficients
- jj=j+1
- do 80 i=jj,n
- am=a(i,j)
- do 60 k=1,n
- a(i,k)=a(i,k)-am*a(j,k)
- 60 continue
- do 70 k=1,m
- b(i,k)=b(i,k)-am*b(j,k)
- 70 continue
- 80 continue
- j=j+1
- enddo
- am=a(n,n)
- if(abs(am).eq.zero)then
- ier=2
- det=0.
- return
- endif
- if(abs(am).le.abs(eps))ier=1
- if(cdet)det=det*am
- c a is now in triangular form
- c compute nth component of solution
- do 90 k=1,m
- b(n,k)=b(n,k)/am
- 90 continue
- c back substitute to compute n-i component
- c i=1,2,3,...
- nn=n-1
- do 120 i=1,nn
- ni=n-i
- do 110 j=1,m
- nj=ni+1
- do 100 ki=nj,n
- b(ni,j)=b(ni,j)-a(ni,ki)*b(ki,j)
- 100 continue
- 110 continue
- 120 continue
- 57return
- end
- subroutine matm(a,ia,m,n,b,ib,l,c,ic)
- implicit real*8(a-h,o-z)
- c arguments
- c a-matrix
- c ia-row dimension of a in calling program
- c m-number of rows of a
- c n-number of columns of a
- c b-matrix
- c ib-row dimension of b in calling program
- c l-number of columns of b
- c c-product matrix: c=a*b
- c ic-row dimension of c in calling program
- c
- dimension a(ia,*),b(ib,*),c(ic,*)
- c c=a*b
- do 10 i=1,m
- do 10 j=1,l
- c(i,j)=0.
- do 5 k=1,n
- 5 c(i,j)=c(i,j)+a(i,k)*b(k,j)
- 10 continue
- return
- end
- 0.22 Location of Piezoelectric Information In
- ANSYS Manuals
- • Index assignment for stress-strain tensor to six-vector: Theory 2.1.
- • Major and Minor Poisson ratios, orthotropic compliance matrices: Theory 2.1.
- • Piezoelectric Solid Element SOLID5: Elements manual 4-39.
- • Piezoelectric Plane Element PLANE13: Elements manual 4-85.
- • Piezoelectric Tetrahedral Coupled Solid Element SOLID98: Elements
- manual 4-653.
- • Piezoelectric Analysis: Procedures Coupled-Field Analysis 8.1, piezoelectric analysis p8-13 to p8-15.
- • Defining matrices: Commands TB and TBDATA, Commands manual.
- 58• Piezoelectrics Theory: Theory Manual 11.1 to page 11-17.
- • Example VM175: Natural Frequency of a Piezoelectric Transducer
- ...(ANSYS Stuff Notebook). Reference: Boucher D, Lagier M, Maerfeld C, IEEE Transactions on Sonics and Ultrasonics, Volume SU-28,
- No. 5 September 1981 pp318-330.
- • Example VM176: Frequency Response of Electrical Admittance for a
- Piezoelectric Transducer, Reference: Kagawa and Yamabuchi, IEEE
- Trans. Sonics and Ultrasonics, V. SU-26, No. 2, March 1979.
- • Example PM13, ANSYS Examples Supplement, Piezoelectric Beam
- Resonator
- 0.23 ANSYS Comparison For A Composite
- Piezoelectric Transducer: Example VM176.
- Reference for the problem: Kagawa and Yamabuchi Finite Element Simulation of a Composite Piezoelectric Transducer IEEE Transactions
- on Sonics and Ultrasonics, Vol. SU-26, No 2 march 1979.
- The transducer consists of cylindrical disks of aluminum, adhesive, PZT,
- adhesive, and aluminum.
- PZT material: NEPEC 6
- Elasticity matrix
- c = 10
- 10
-
-
-
-
-
-
-
-
- 12.8 6.8 6.6 0 0 0
- 6.8 12.8 6.6 0 0 0
- 6.6 6.6 11 0 0 0
- 0 0 0 2.1 0 0
- 0 0 0 0 2.1 0
- 0 0 0 0 0 2.1
-
-
-
-
-
-
-
-
- 59Piezoelectric matrix (C oulomb/M eter
- 2
- )
- e =
-
-
-
-
-
-
- 0 0 −6.1
- 0 0 −6.1
- 0 0 15.7
- 0 0 0
- 0 0 0
- 0 0 0
-
-
-
-
-
-
- Dielectric Matrix (F arad/M eter)
- = 10−9
-
-
-
- 8.7969 0 0
- 0 8.7969 0
- 0 0 8.7969
-
-
-
- See ANSYS notebook for more details.
- 600.24 Piezoelectricity Bibliography
- [1]Agarwal Bhagwan D, Broutman Lawrence, Analysis And Performance
- Of Fiber Composites.
- [2]Ahmed F R, Crystallographic Computing, Proceedings International
- Summer School, Linda Hall Library.
- [3]Allik H, Hughes J R, Finite Element Method For Piezoelectric Vibration, International Journal of Numerical Methods For Engineering, V.
- 2, pp 151-157, 1970, (This is the formulation of the problem that is implemented in ANSYS.).
- [4]Ashton J E, Whitney J M, Theory Of Laminated Plates, Linda Hall
- Library, 1979.
- [5]Ashton T E, Halpin T C, Petit P H, Primer On Composite Materials
- Analysis, Technomic, Stamford Conn., 1969.
- [6]Auld B A, Acoustic Fields And Waves In Solids, Volumes I and II.
- [7]Billington E W, Introduction To The Mechanics And Physics Of
- Solids, AlliedSignal Library, QA808 .2, 1986, A Mathematical Book. Von
- Mises Yield Criterion. Von Mises Stress.
- [8]Bottom Virgil E, The Theory And Design Of Quartz Crystal Units,
- 2nd Ed., 1974, (Self Published), Linda Hall, (Piezoelectric Transducers.).
- [9]Boucher D, Lagier M, Maerfeld, Computation Of The Vibrational
- Modes For Piezoelectric Array Transducers Using A Mixed Finite
- Element-Perturbation Method, IEEE Transactions on Sonics And Ultrasonics, V. Su28, No. 8, Sept 81.
- [10]Brebbia, Dewilde,Blain, Computer Aided Design In Composite Material Technology, TA 418.9 .c6 I585, 1988, Linda Hall.
- [11]Buchanon Relva C, Editor, Ceramic Materials For Electronics, 2nd
- Ed., 1991, AlliedSignal Library, (Piezoelectricity.).
- [12]Buerger, Martin, Introduction To Crystal Geometry.
- [13]Cady Walter Guyton, Piezoelectricity, Volumes I and II, Dover, 1964,
- 61KCMO Library.
- [14]Cady Walter Guyton, The Piezoelectric Resonator, In: Physical
- Acoustics, R. Bruce Lindsey Editor, (Benchmark Papers In Acoustics).
- [15]Clough R W, Penzien J, Dynamics Of Structures, McGraw-Hill 1972,
- AlliedSignal Library, (Rayleigh Damping, Piezoelectricity.).
- [16]Cracknell A P, Ultrasonics, Wykeham Publications, 1980 AlliedSignal
- Library.
- [17]Crandall B C, Lewis James, Editors, Nanotechnology, Article: John
- Foster, p17, Scanning Tunneling Microscope (STM), (Uses Piezoelectric Control,), 1992, MIT Press.
- [18]Cullity, Elements Of X-Ray Diffraction, Addison-Wesley, 1956.
- [19]Cummings James R, Predicting The Effect Of Thickness Of Piezoelectric Plates On The Performance Of The Ultrasonic Traveling
- Wave Motor, U. Mo. (Rolla,), May 1993.
- [20]Cummings James R, Stutts Daniel S, Dharani L R, Effects Of Material And Geometric Characteristics On The Performance Of A
- Traveling-wave Motor, U. MO. Rolla Report, 11-9-93.
- [21]Cummings Robert James, Analysis Of The Performance And Contact Behavior Of The Piezoelectric Traveling-wave Motor, Masters
- Theses, University Of Missouri-Rolla MRTC Manufacturing Research And
- Training Center, 1994.
- [22]Emery James D, Elasticity, Unpublished Document.
- [23]Emery James D, Electomagnetic Theory, Unpublished Document.
- [24]Emery James D, Transducer Equivalent Circuits, Unpublished Document.
- [25]Emery James D, Piezo Notes I, Unpublished Document.
- [26]Emery James D, Piezo Notes II, Unpublished Document.
- [27]Flynn Anita, Torque Production In Ultrasonic Motors, MIT Arti-
- 62ficial Intelligence Laboratory, January 9, 1994, (Piezoelectric Motor.).
- [28]Flynn Anita M, Piezoelectric Ultrasonic Micromotors, PhD Thesis,
- MIT, June 1995.
- [29]Fulton Langdon H, Techniques And Applications Of The Gas Squeeze
- Film Bearing, Masters Thesis, Moore School, U. Pennsylvania, Dec 1967,
- (Piezoelectric Application. Now At Martin-Marietta Communications Systems, Camden NJ).
- [30]Gooberman G L, Ultrasonics, 1968, Acoustic Impedance, Transmission,
- Lines, Transducers, Equivilent Circuit As Transmission Line, Q Of Transducer.
- [31]Goree, Pagano-Goree Free Edge Stress, (Discussion, Goree: Singular
- Elements In Abaqus Are Needed, Disagreement With Whitney.).
- [32]Hagedorn P, Wallashek J, Traveling Wave Ultrasonic Motors, Part
- I: Working Principle And The Mathematical Modeling Of The Stator, J. Of Sound And Vibration, V. 155, No. 1, pp 31-46, 1992.
- [33]Hagood N, Chung W,Von Flotow A, Modeling Of Piezoelectric Actuator Dynamics For Active Structural Control, J. Intell. Mat. Syst.
- And Structures, V. 1, pp327-354, July 1990, (Hamilton’s Principal Modified
- For General Electromechanical Systems.).
- [34]Hagood Nesbit, Mcfarland Andrew, Modeling Of A Piezoelectric Rotary Ultrasonic Motor, IEEE Trans. Ultrasonics Ferroelectrics And Frequency Control, V. 42, No. 2, March 1995, Nesbit was Anita Flynn Collegue
- at MIT. Rayleigh-Ritz Method, which includes, Electrical Energy.
- [35]Hauptman, Herbert, Crystal Structure Determination, Linda Hall,
- QD911.h33, 1972, Mathematical Biophysics Department, Medical Foundation Of Buffalo, Cosine Semiinvariants.
- [36]Heising Raymond A, Quartz Crystals For Electrical Circuits: Their
- Design And Manufacture, Van Nostrand, 1946, Reprinted by Electronic
- Industries Association, 2001 Eye St, NW, Washington DC 20006, 1978, 1982,
- (Piezoelectric Equivalent Circuits.).
- [37]Hirose, Takahashi, Uchino, Aoyagi, Tomakawa, Electromechanical Prop-
- 63erties Of PbZro3-pbzrtio3-pb(mn(1/3)sb(2/3)o3 Ceramics Under
- Vibration Level Change, Mat. Res. Soc. Symp. Proc., V. 360, 1995,
- Materials Research Society.
- [38]Hirose, Takahashi, Uchino, Aoyagi, Tomakawa, Measuring Methods
- For High-Power Characteristics Of Piezoelectric Materials, Mat.
- Res. Soc. Symp. Proc., V. 360, 1995, Materials Research Society.
- [39]Hossack John A, Hayward Gordon, Finite-Element Analysis of 1-3
- Composite Transducers, IEEE Transactions on Ultrasonics, Ferroelectrics,
- and Frequency Control, V. 38, N0. 6, November 1991, (Uses ANSYS.).
- [40]Inman Daniel, Engineering Vibration, MatLab Disk, 1994, Chapter:
- Experimental Modal Analysis.
- [41]Institute of Radio Engineers, IRE Standards on Piezoelectric Crystals: Determination of the Elastic, Piezoelectric, and Dielectric
- Constants, The Electromechanical Coupling Factor, 1958, Proc. IRE,
- V. 46, pp764-78.
- [42]Jaffe Bernard, Cook William, Jaffe Hans, Piezoelectric Ceramics, Academic Press, 1971, Linda Hall, TK7871.15.C4 J3, Definitions, Symmetry,
- Constants, Measurements, Hysteresis.
- [43]Johnson K L, Contact Mechanics, Linda Hall Library.
- [44]Jones, Acoustic And Electromagnetic Waves, Oxford.
- [45]Kagawa, Yamabuchi, Finite Element Simulation of a Composite
- Piezoelectric Transducer, IEEE Transactions on Sonics and, Ultrasonics,
- V. SU-26, No. 2 march 1979, (ANSYS example VM176.).
- [46]Kikuchi And Oden, Contact Problems In Elasticity: A Study Of
- Variational Inequalities And Finite Element Methods, Linda Hall,
- QA931.k47 1988, (SIAM), Society For Industrial And Applied Mathematics.
- [47]Kittle, Solid State Physics, (Piezoelectric Equations.).
- [48]Koehler D R, Radial Vibration Modes In Thin Plates Of BaT iO3
- And LiNBO3, Memo, Sandia National Laboratory, October 16, 1989.
- 64[49]Koiter W T , Miknailor G K, Theory Of Shells.
- [50]Kolsky, Stress Waves In Solids, Dover.
- [51]Kompaneyts A S, Theoretical Physics, Dover, 1961.
- [52]Lass Victor, Vector And Tensor Analysis, (Relation Between Mechanical, Electric, And Magnetic Energy.).
- [53]Lazan B J, Damping Of Materials And Members In Structural
- Mechanics, Oxford 1968.
- [54]Lerch, R, Simulation Of Piezoelectric Devices By Two And Three
- Dimensional Finite Elements, IEEE Trans. On Ultrasonics Ferroelectrics
- And Freq. Control, V. 37, No. 2, May 1990.
- [55]Levich B G, Theoretical Physics, Volumes I, Ii, Iii, Wiley-Interscience
- 1971.
- [56]Lur’e A L, Three-dimensional Problems Of Elasticity, (Basis Of
- James Cummings Rolla Analysis Of Tooth Contact In Piezo Motor).
- [57]Mansfield, E H, The Bending And Stretching Of Plates, (The Small
- Deflection Theory Of Plates Is Analogous To Beam Small, Deflection Theory. Gaussian And Mean Curvature, Where Curvature Is Taken To, Be
- Approximated By The 2nd Order Derivatives. Twist Is The Cross Derivative, Transformation Matrix For Curvatures Handled As In JRC (above).
- [58]Marsden Jerrold, The Mathematical Theory Of Elasticity, (Contains Much Differential Geometry).
- [59]Martin, Transformation Geometry, (Symmetry Groups, Transformations).
- [60]Mason Warren P, Piezoelectric Crystals and Their Application to
- Ultrasonics, Van Nostrand, 1950.
- [61]Mason Warren P, Physical Acoustics, 1964 Academic, AlliedSignal Library, QC225.m3, (Piezoelectric Actuators.).
- [62]Mcfarland, Smith, Bernhart, Analysis Of Plates, Linda Hall Library.
- 65[63]McLachlan N W, Theory Of Vibrations, Circular Membrane, Circular
- Plate, Bessel Functions p 129-144.
- [64]Meirovitch Leonard, Elements Of Vibration Anlysis, Mcgraw-Hill,
- 1975.
- [65]Meirovitch, Leonard, Analytical Methods Of Vibration, Vibration
- Of Plates p 179, Eigenvalues, Rayleigh Quotient, The Biharmonic Equation.
- [66]Mentesana C P, Optical Stronglink Development And Piezoelectric Motor Evaluation, AlliedSignal KCD, Kcp-613-4573, May 1992.
- [67]Mercer C D, Reddy B D, Eve R A, Finite Element Method For Piezoelectric Media, UCT/CSIR Applied Mechanics Research Unit, Technical
- Report No. 92, April, 1987.
- [68]Merhaut Josef, Theory Of Electroacoustics, 1976, Czech Book, Johnson County Library, (Piezoelectric Transducers.).
- [69]Mikhlin, S.g, Variational Methods In Mathematical Physics, Linda
- Hall Library, 1964.
- [70]Mizushima Masataka, Theoretical Physics, John Wiley, 1972, AlliedSignal, (From Classical Mechanics To General Relativity, Relativistic Quantum Mechanics And Group Theory.).
- [71]Moore And Christopher Davis And Coplan, Building Scientific Apparatus, (Experimental Techniques.).
- [72]Morgan Matroc Incorporated, Guide To Modern Piezoelectric Ceramics, Catalog, Vernitron Division.
- [73]Morse, Philip M, Vibration And Sound.
- [74]Musikant Solomon, What Every Engineer Should Know About Ceramics, 1991, Marcel Dekker, AlliedSignal Book.
- [75]Newnham R E, Trolier-McKinstry S, Giniewicz J R, Piezoelectric, Pyroelectric And Ferroic Crystals, J. Material Education, 15, pp 189-223
- (1993), (Reprint: Penn State MRL Annual Report To ONR 1994, Appendix
- 661).
- [76]Nye J F, Physical Properties Of Crystals, QD931 .N8, 1957, 1987.
- [77]Ostergard D, Pawlak T, Three-Dimensional Finite Elements For
- Analyzing Piezoelectric Structures, Proceedings IEEE Ultrasonics Symp.,
- Williamsburg, Va, 1986, pp 639-642.
- [78]Paganno N J, Pipes R B, Interlaminar Stresses In Composite Laminates Under Uniform Axial Extension, Journal Of Composite Materials, V. 4, 1970, pp 538-548.
- [79]Paganno N J, Pipes R B, The Influence Of Stacking Sequence On
- Laminate Strength, Journal Of Composite Materials, V. 5, 1971, pp 50-57.
- [80]Panasonic, Ultrasonic Motor, Panasonic Electric Motor Division, Matsushita Electric Industrial Co. Ltd., (Equivalent Circuit.).
- [81]Parker Sybyl, Solid State Physics Sourcebook.
- [82]Press, Flannery, Teukolsky, Numerical Recipes in Fortran, (Subroutines For Computing Bessel Functions.).
- [83]Pressly Robert B, Mentesana Charles P, Piezoelectric Motor Development At AlliedSignal Kansas City Division, KCP-613-5515, November, 1994.
- [84]Puppo A. H. Evenson H A, Journal Of Composite Materials, V. 4,
- 1970, pp 201-214.
- [85]Raju P. Narayana, Vibration Of Annular Plates, Journal Of The
- Aeronautical Society Of India, V. 14, No. 2, May, 1962, (Boundary Conditions For Maple Motor Code).
- [86]Ramachandran G N , Srinivasan R, Fourier Methods In Crystallography, Linda Hall Library, 1970.
- [87]Rayleigh Lord, The Theory Of Sound, Volumes I and II, Dover, (Vibrations Of Plates: Chapter 10, p 352, Origin of Rayleigh Damping Concept).
- 67[88]Roiguiskis, Bansevicius, Barauskas, Kulviets, Vibromotors For Precision Microrobots, AlliedSignal Library, (Many Kinds Of Piezoelectric
- Motor Designs.).
- [89]Saigoh Hiroaki, Kawasaki Mayumi, Maruko Nobuhiro, Kanayama Kouichi,
- Multilayer Piezoelectric Motor Using The First Longitudinal And
- Second Bending Vibrations, Japanese J Applied Physics, V. 34, 1995,
- pp2760-2764.
- [90]Sands Donald E, Introduction To Crystallography, 1975, Dover.
- [91]Sashida Toshiiku, Kenjo Takashi, An Introduction To Ultrasonic
- Motors, Oxford U. Press 1993, Piezoelectricity.
- [92]Sawyer C B, Tower C H, Phys. Rev. 35, (1930) pp269-73, (Technique For Displaying Ferroelectric-Piezoelectric Hysteresis Curves.).
- [93]Sherrit S, Gauther N, Wiederick H D, Mukherjee B K, Accurate Evaluation Of The Real And Imaginary Material Constants For A Piezoelectric Resonator In The Radial Mode, Ferroelectrics, 1991, V. 119,
- pp17-32.
- [94]Shields John Potter, Basic Piezoelectricity, 1966, Sams, QC595 .S4,
- Linda Hall Library.
- [95]Smits Jan G, Iterative Method For The Accurate Determination
- Of The Real And Imaginary Parts Of The Materials Coefficients
- Of Piezoelectric Ceramics, Trans. Sonics Ultraacoustics. V. Su-23, No.
- 6, Nov. 1976, pp393-402.
- [96]Soedel Werner, Vibrations Of Shells And Plates, 1981. Second Edition 1993, University Illinois At Chicago.
- [97]Sokolnikoff I S, Mathematical Theory Of Elasticity, 1956, (Biharmonic Equation p77, Two Dimensional Problems Ch. 5, Finite Differences,
- Relaxation Methods, pp442-454.).
- [98]Southwell R V, Theory Of Elasticity.
- [99]Stoker, Nonlinear Vibrations.
- 68[100]Stutts Daniel, Loss Factors, FAX: Feb 23, 1996, Various Materials
- Loss Coeficients vs Young Modulus, Comparison Of Damping for a Variety
- of Metals, Magnetoeleastic Damping In Ferromagnetic Metals, Internal Friction Vs Strain Amplitude, Experimental Setup With Pucot Drive Crystal
- And Specimin.).
- [101]Stutts Daniel, Modal Analysis Of The Free-Free Rod With Damping, FAX: April, 9 1996, (See Piezo96 Notebook.).
- [102]Stutts Daniel, A Simple Example Of The Relationship Between
- Electromechanical Coupling And Measured Impedance, Unpublished
- Document, University of Missouri at Rolla, Mechanical Engineering Department, March 1, 1995.
- [103]Stutts Daniel, The Free-free Annular Plate, Maple Program And
- Document, U. Mo. Rolla Mech. Eng. Dept, January,1994.
- [104]Stutts Daniel S, Friend James R (Formerly Cummings), Quarterly Report: Piezoelectric Motor Project, Oct. 2 1995 (tooth Motion, Asymmetry, Maple Conference, Contact Mech, Web Page).
- [105]Takahashi Sadayuki, Herose Seiji, Uchino Kenji, Oh Ki-Young, Electromechanical Characteristics Of Lead-Zirconate-Titanate Ceramics
- Under Vibration Level Change, 1995 IEEE.
- [106]Takuro Ikeda, Fundamentals Of Piezoelectricity,, (Electromechanical Coupling Coefficient, X-cut, Y-cut Plate, Equivalent Circuit. p84.).
- [107]Termin, Radio Engineering, (Equivalent Circuit Of Piezo Oscillator).
- [108]Tiersten H F, Linear Piezoelectric Plate Vibration, Plenum Press,
- 1969, pp33-99, (Fundamental Equations And Equivalent Circuit.).
- [109]Timoshenko And Goodier, Theory Of Elasticity, Third Edition.
- [110]Timoshenko, And Woinowsky-Krieger, Theory Of Plates And Shells,
- 2nd Ed.
- [111]Tomikawa Y, Ueha S, Ultrasonic Motors: Theory And Application, Oxford 1993.
- 69[112]Tuinenga Paul, Spice, A Guide To Circuit Simulation And Analysis Using Pspice.
- [113]Tzou H S, Piezoelectric Shells, Kluwer Academic Publishers, 1993.
- [114]Urick Robert J, Principles Of Underwater Sound, 2nd Ed., McGrawHill, 1975, (Piezoelectric Transducers.).
- [115]Van Randeraat J, Setterington R E, Piezoelectric Ceramics, London,
- Mullard, Linda Hall Library, 1974.
- [116]Voyiadjis, Karamanlidis, Editors, Advances In The Theory Of Plates
- And Shells, Linda Hall Library.
- [117]Wallashek Jorg, Piezoelectric Ultrasonic Motors, Conference On
- Mechatronics And Robotics, Duisburg/Moers, Germany, Sept 27-29, 1993
- pp107-125.
- [118]Webb S, The Physics Of Medical Imaging, 1988, Ultrasound, NMR,
- CT, Tomography.
- [119]Weinberger, Hans, Partial Differential Equations, (Sturm-Liouville
- Problems, pp182-187, Circular Membrane, Bessel Functions.).
- [120]Weinberger, H F, Variational Methods In Boundary Value Problems, 1961.
- [121]Wert, Thomson, Physics Of Solids.
- [122]Whitney J M, Browning C E, Journal Of Composite Materials, V.
- 6, April 1972, pp 50-57.
- [123]Whitney J M, Stansbarger D L, Howell H B, Journal Of Composite
- Materials, V. 5, April 1971, pp24-34.
- [124]Whitney James M, Structural Analysis Of Laminated Isotropic
- Plates, 1987, Technomic, (Includes Lampcal Software.).
- [125]Whitney, Pipes, Experimental Mechanics Of Fiber Reinforced
- Composite Materials, 1982, T-C Publishers.
- [126]Willmore, T J, Tensors As Tensor Products, Linda Hall Library,
- 701959.
- [127]Woolett Ralph S, Theory Of Piezoelectric Flexural Disk Transducers With Applications To Underwater Sound, USL Report No.
- 490, U. S. Navy Underwater Sound Laboratory, Fort Trumbull, New London
- Conn, 1960, S-F001 03 04-1.
- [128]Wooster, W A, Breton A, Experimental Crystal Physics, KCMO
- Library.
- [129]Yang, Variational Formulation Of Piezoelectric Elements.
- [130]Ziman J M, Principles Of The Theory Of Solids, Cambridge, 1964,
- (Second Edition 1979).
- 71