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Equation of Piezoelectricity

 

The equation of piezoelectricity represents the relationship of stress T, strain S, electric field E, and electric flux density D.

Strain and stress are explained in detail at Strain Type and Stress Type respectively.

Here, strain, stress, electric field, and electric flux density are represented in the form of vector.

 

 

 

The equations of piezoelectricity are the elastic modulus (compliance matrix (s) or stiffness matrix (c)), the relative permittivity matrix ε (or inverse matrix of relative permittivity β), the equations of piezoelectric constants (e, g, h, d) as well as the above. There are four types of equations as below.

 

e-type

g-type

h-type

d-type

 

The suffix, t in et, gt, ht, dt indicates a transpose of the matrix.

d-type

For frequently used d-type, the components of the matrix correspond to the input items on the dialog box as below.

Input of the elastic compliance matrix (s)

The elasticity matrix is symmetric. In the input dialog box for the piezoelectricity, enter the lower left side only as below.

 

 

xx

yy

zz

yz

zx

xy

xx

s11

--

--

--

--

--

yy

s21

s22

--

--

--

--

zz

s31

s32

s33

--

--

--

yz

s41

s42

s43

s44

--

--

zx

s51

s52

s53

s54

s55

--

xy

s61

s62

s63

s64

s65

s66

 

Input of the piezoelectric constant d

 

x

y

z

yz

zx

xy

x

d11

d12

d13

d14

d15

d16

y

d21

d22

d23

d24

d25

d26

z

d31

d32

d33

d34

d35

d36

 

Input of the relative permittivity matrix

The relative permittivity matrix is symmetric. In the input dialog box for the piezoelectricity, enter the lower left side only as below.

 

x

y

z

x

ε11

--

--

y

ε21

ε22

--

z

ε31

ε32

ε33

 

 

e-type

For frequently used e-type, the components of the matrix correspond to the input items on the dialog box as below.

 

Input of the elastic stiffness matrix

The elasticity matrix is symmetric. In the input dialog box for the piezoelectricity, enter the lower left side only as below.

 

 

xx

yy

zz

yz

zx

xy

xx

c11

--

--

--

--

--

yy

c21

c22

--

--

--

--

zz

c31

c32

c33

--

--

--

yz

c41

c42

c43

c44

--

--

zx

c51

c52

c53

c54

c55

--

xy

c61

c62

c63

c64

c65

c66

 

Input of the piezoelectric constant e

 

x

y

z

yz

zx

xy

x

e11

e12

e13

e14

e15

e16

y

e21

e22

e23

e24

e25

e26

z

e31

e32

e33

e34

e35

e36

 

Input of the relative permittivity matrix

The relative permittivity matrix is symmetric. In the input dialog box for the piezoelectricity, enter the lower left side only as below.

 

x

y

z

x

ε11

--

--

y

ε21

ε22

--

z

ε31

ε32

ε33