Learning Forum

[hossein__mht]

Hello

I've simulated a PZT-5H in ANSYS APDL. All the inputs of material properties are according to data sheet. The element type is SOLID226 and the KEYOPT(1) is 1001. The potential difference is 100 and 0 Volt in z direction and The permittivity in this simulation is at constant strain. The piezo should have 56 micro-meters if we apply these voltages but it has 0.064 micro-meters! I've written the session editor and uploaded some images of my simulation and the data sheet. Could anyone tell me the problem?

thanks a lot

Best regards; Mohammad Hossein Talebi

----------------------------------------------------------------------------------------------------

/PREP7  

!*  

ET,1,SOLID226,11

!*  

KEYOPT,1,1,1001 

KEYOPT,1,2,0

KEYOPT,1,4,0

KEYOPT,1,5,0

KEYOPT,1,6,0

KEYOPT,1,7,0

KEYOPT,1,8,0

KEYOPT,1,9,0

KEYOPT,1,10,0  

KEYOPT,1,15,0  

!*  

!*  

TB,ANEL,1,1,21,1

TBTEMP,0

TBDATA,,16.5e-12,,-9.1e-12,,,  

TBDATA,,16.5e-12,-9.1e-12,,,,20.7e-12  

TBDATA,,,,,43.5e-12,,  

TBDATA,,43.5e-12,,33e-12,,, 

MPTEMP,,,,,,,,  

MPTEMP,1,0  

MPDATA,DENS,1,,7800 

MPTEMP,,,,,,,,  

MPTEMP,1,0  

MPDATA,PERX,1,, 

MPDATA,PERY,1,, 

MPDATA,PERZ,1,,1762.583881574612

TB,PIEZ,1,,,1  

TBMODIF,1,1,

TBMODIF,1,2,

TBMODIF,1,3,-320e-12

TBMODIF,2,1,

TBMODIF,2,2,

TBMODIF,2,3,-320e-12

TBMODIF,3,1,

TBMODIF,3,2,

TBMODIF,3,3,650e-12 

TBMODIF,4,1,

TBMODIF,4,2,

TBMODIF,4,3,

TBMODIF,5,1,

TBMODIF,5,2,

TBMODIF,5,3,

TBMODIF,6,1,

TBMODIF,6,2,

TBMODIF,6,3,

BLC4,-0.0025,-0.0025,0.005,0.005,0.036  

! /VIEW,1,1,1,1  

! /ANG,1  

! /REP,FAST  

! /DIST, 1 ,1.082226,1

! /REP,FAST  

ESIZE,0.001,0,  

MSHAPE,0,3D 

MSHKEY,1

!*  

CM,_Y,VOLU  

VSEL, , , ,    1 

CM,_Y1,VOLU 

CHKMSH,'VOLU'  

CMSEL,S,_Y  

!*  

VMESH,_Y1  

!*  

CMDELE,_Y  

CMDELE,_Y1  

CMDELE,_Y2  

!*  

! /VIEW,1,1  

! /ANG,1  

! /REP,FAST  

! /DIST, 1 ,1.082226,1

! /REP,FAST  

! /DIST, 1 ,1.082226,1

! /REP,FAST  

FLST,2,96,1,ORDE,2  

FITEM,2,1  

FITEM,2,-96 

/UI,MESH,OFF

!*  

/GO 

D,P51X, , , , , ,UX,UY,UZ, , ,  

FLST,2,96,1,ORDE,2  

FITEM,2,1  

FITEM,2,-96 

/GO 

!*  

D,P51X,VOLT,100 

FLST,2,96,1,ORDE,2  

FITEM,2,97  

FITEM,2,-192

/GO 

!*  

D,P51X,VOLT,0  

! /VIEW,1,1,1,1  

! /ANG,1  

! /REP,FAST  

! SAVE, 5h_loading,db,D:UniversityProjectCADPiezoapdl 

! LGWRITE,'5h_loading','lgw','D:UniversityProjectCADPiezoapdl',COMMENT

! /VIEW,1,1  

! /ANG,1  

! /REP,FAST  

FLST,4,96,1,ORDE,2  

FITEM,4,1  

FITEM,4,-96 

CP,1,VOLT,P51X  

FLST,4,96,1,ORDE,2  

FITEM,4,97  

FITEM,4,-192

! /VIEW,1,1,1,1  

! /ANG,1  

! /REP,FAST  

! /DIST, 1 ,0.924021,1

! /REP,FAST  

! /DIST, 1 ,0.924021,1

! /REP,FAST  

! /DIST, 1 ,0.924021,1

! /REP,FAST  

! /DIST, 1 ,1.082226,1

! /REP,FAST  

! /DIST, 1 ,1.082226,1

! /REP,FAST  

! /VIEW,1,1  

! /ANG,1  

! /REP,FAST  

! /VIEW,1,1,1,1  

! /ANG,1  

! /REP,FAST  

! /VIEW,1,1  

! /ANG,1  

! /REP,FAST  

FLST,4,96,1,ORDE,2  

FITEM,4,97  

FITEM,4,-192

CP,2,VOLT,P51X  

! /VIEW,1,1,1,1  

! /ANG,1  

! /REP,FAST  

! /VIEW,1,1  

! /ANG,1  

! /REP,FAST  

! /VIEW,1,1,1,1  

! /ANG,1  

! /REP,FAST  

FINISH  

[ErKo]

If one takes say the properties for pzt5h say from here (you used a different form in ansys): https://www.globalspec.com/reference/48151/203279/appendix-2-electroelastic-material-constantsnnThen the displacement on applied voltage in a uniaxial bar/plate (dimensions: LxWxH) is given by:nAxial displ. = (Voltage applied)/(g33 * Elastic constant in axial dir)ng33 is about 0.017 for PZT5H, and E_axial ~ 11E10 Pa.nnUsing these values in the equation above gives an axial displacement of about 5.6E-8 m which is close to the Ansys results. So that is OKnnThank you and kind regardsnnErikn

[ErKo]

HinIf we take the PZT5H (prefer working with these types of constants) from here: https://www.globalspec.com/reference/48151/203279/appendix-2-electroelastic-material-constantsnwe can then calculate the axial displacement in a uniaxial case for a bar.nnThe axial displ. is = (Voltage applied)/(g33*E_axial).nnFor pzt5h g33 ~ 0.017 (Vm/N) and E_axial ~11E10 Pa, giving a displ. of about 5.6E-8 m with a 100 V potential diff. across the bar/plate, which is what one would get with ansys.nnThank you and hope this helpsnnEriknn

[hossein__mht]

Dear Erik nThank you so much for your answer to my question. It helped me so much and I'm so grateful!nTo other people who are working on this subject, It's better to notice that the longitudinal displacement of longitudinal actuators is = (n)(d_33)(V)nn is the Number of stacked ceramic layers, d_33 is Longitudinal piezoelectric large-signal deformation coefficient [m/V], V is Operating voltage [V].nThis website may help you so much:nThanks and hope this helpsnBest regards, Mohammad Hossein Talebin

[ErKo]

Many thanks.Erikn