压电分析问题请教

ysuylj

第一、计算结果发现，和压电叠层的基地层Si梁没有受到压电层的作用，怎么样才能将压电层的效应传递到Si层（SOLID45），注意压电层（SOLID5）和Si层有电极PT（SHELL41），压电层最上面也有Pt电极层。
第二、这个文件中的模型是我建的，另外我觉得给电极层划分网格的时候有问题，因为选择的时候我用ASEL,s,loc,z,tbeam，这样就把SI的上面、电极面和压电层的下面三个面给选中了，这样划分网格对不对？但是我采用直接选择电极层划分网格加电压载荷，最后计算结果，压电层根本没有反映，或者说问题出在电压根本没有加到压电材料上。
请大虾有时间做做这个例子。后面有源文件。我的邮箱是ysuylj@126.com
/TITLE,Modal and harmonic analysis of a Si beam actuated by a PZT thin film
tstep = 10.0E-6 ! Technology step
lbeam = 200E-6 ! Length of beam
wbeam = 50E-6 ! Width of beam
tbeam = 10.0E-6 ! Thickness of beam
l_PZt = lbeam-2*tstep ! Length of PZt on beam
w_PZt = wbeam-2*tstep ! Width of PZt layer
t_PZt = 2.0E-6 ! Thickness of piezoelectric actuator ceramic
l_PtB = lbeam-tstep ! Length of bottom Pt layer on beam
l_PtT = lbeam-3*tstep ! Length of top Pt layer on beam
w_PtB = wbeam-tstep ! Width of bottom Pt layer
w_PtT = wbeam-3*tstep ! Width of top Pt layer
t_Pt1 = 0.07E-6 ! Thickness of lower platinum electrode
t_Pt2 = 0.1E-6 ! Thickness of upper platinum electrode
/PREP7 ! Enter preprocessor
/COM, ! Define element tables
ET,1,5,0 ! 8-node coupled field solid with all DOFs, for PZt
ET,2,45 ! 8-node solid with displacements (UX,UY,UZ) used for Si
ET,3,41 ! Membrane Shell (Pt layers)
/COM, !PZT piezo ceramic layer material properties (material 1)
MP,DENS,1,7400 ! Yuhuan Xv, Ferroelectric materials and their applications, North-Holland 1991, Pb(Zr0.53 Ti0.47)O3
MP,PERX,1,4.8E-9 ! Permittivity of piezoceramic
MP,PERY,1,4.8E-9 ! Physical Acoustic Principles and Methods
MP,PERZ,1,4.8E-9 ! Warren P. Mason Volume 1 Academic Press 1964
TB,PIEZ,1 ! Piezoelectric "e" matrix of piezoceramic
TBDATA,3,-1.86
TBDATA,6,-1.86 ! Physical Acoustic Principles and Methods
TBDATA,9,9.0 ! Warren P. Mason Volume 1 Academic Press 1964
TBDATA,11,9.8
TBDATA,13,9.8
TB,ANEL,1 ! Stiffness "c" matrix of piezoceramic
TBDATA,1,13.5E10,6.74E10,6.81E10
TBDATA,7,13.5E10,6.81E10 ! Physical Acoustic Principles and Methods
TBDATA,12,11.3E10 ! Warren P. Mason Volume 1 Academic Press 1964
TBDATA,16,2.22E10
TBDATA,19,2.22E10
TBDATA,21,3.355E10
MP,MURX,1,0 ! Bogey material properties to suppress error messages
MP,KXX,1,0 ! Bogey material properties to suppress error messages
/COM, !Si isotropic material properties (material 2)
MP,EX,2,120e9 ! Young's module of Si for isotropic 120e9 originally
MP,NUXY,2,0.42 ! Poisson's ration of Si
MP,DENS,2,2329 ! Density of Si
/COM, !Platinum electrode material properties (material 3)
MP,EX,3,95e9 ! Young's modulus of Pt
MP,NUXY,3,0.33 ! Poisson's ration of of Pt
MP,DENS,3,21450 ! Handbook of chemistry and physics
R,1,t_Pt1 ! Real constant 1; thickness of lower Pt electrode
R,2,t_Pt2 ! Real constant 2; thickness of upper Pt electrode
FINISH ! Quit processor
/COM, ! Creat beam,PZT,PT geometry model
/COM, ! Creat beam,PZT,PT geometry model
/PREP7 ! Enter preprocessor
BLOCK,0,lbeam,0,wbeam,0,tbeam ! Creat Si-beam model (material 2)
wpoffs,0,0,10e-6 ! Offset working plane 10e-6 in Z-coordinate location
BLC4,0,0,l_ptb,w_ptb ! Creat bottom Pt electrod (material 3
BLC4,0,0,l_pzt,w_pzt,t_pzt ! Creat PZT piezoelectric model(material 1)
wpoffs,0,0,t_pzt ! Offset working plane t_PZT in Z-coordinate location
BLC4,0,0,l_ptt,w_ptt ! Creat top electrod (material 3)
WPAVE,0,0,0 ! Offset working plane to original place
/COM, ! Meshing for three materials
ESIZE,2*tstep ! Set element size for mesh
/COM, !Meshing for PZT beam volumes
VSEL,S,LOC,Z,tbeam,tbeam+t_pzt ! Select from item=LOC component=Z Between tbeam(10e-6) and tbeam+t_pzt
TYPE,1 ! Use element table type 1 for meshing (PZT)
MAT,1 ! Use material 1 attributes for meshing (PZT)
VMESH,ALL ! Mesh all selected volumes
/COM, ! Meshing for Si beam volumes
VSEL,S,LOC,Z,0,tbeam ! Select Si volumes
TYPE,2 ! Use element table type 2 for meshing (Si)
MAT,2 ! Use material 2 attributes for meshing (Si)
VMESH,ALL
/COM, ! Mesh bottom Pt electrode and define component by nodes
TYPE,3 ! Use element table type 3 for meshing (Pt)
MAT,3 ! Use material 3 attributes for meshing (Pt)
ASEL,S,LOC,Z,TBEAM ! Select upper electrode areas
REAL,1 ! SET real constant to 1
AMSEH,ALL ! Mesh for bottom layer(Did it mesh area 6,7,8? Is it wrong?)
NSLA,S,1 ! Select nodes based on selected areas
CM,bot_elec,NODE ! Top electrode node component
CP,1,VOLT,ALL ! Couples volt DOF on top electrode
*GET,nel1,NODE,,NUM,MIN ! Get lowest node number of selected node set
ASEL,S,LOC,Z,TBEAM+T_PZT ! Select upper electrode areas (Two areas (13,14) been selected,how to select area 14-pt?)
REAL,2 ! Real constant set 2 (top Pt electrode thickness)
AMESH,ALL ! Mesh all selected areas
NSLA,S,1 ! Select nodes based on selected areas
CM,top_elec,NODE ! Top electrode node component
CP,2,VOLT,ALL ! Couples volt DOF on bottom electrode
*GET,nel2,NODE,,NUM,MIN ! Get lowest node number of selected node set
ALLSEL ! Select everything
FINISH ! Exit active processor
!static analysis
/SOLU ! Enter solution processor
D,top_elec,VOLT,10.0 ! Assign zero potential to a node of top electrode
D,bot_elec,VOLT,0.0 ! Assign zero potential to a node of top electrode
NSEL,S,LOC,X,0 ! Select nodes at beam attachment point
D,ALL,UX,,,,,UY,UZ ! Remove displacement DOFs from selected nodes
NSEL,ALL ! Select all nodes
NSEL,S,LOC,Y,0 ! Select nodes at beam centre line
DSYM,SYMM,Y ! Define symmetry boundary conditions
NSEL,ALL ! Select all nodes
SOLVE ! Solve current load step
FINISH ! Exit active processor
/POST1 ! Enter general post-processor
/TITLE,Electric potential distribution in model for static voltage of 10 V
PLNSOL,VOLT ! Plot contours of voltage DOF
/WAIT,3
/TITLE,Vertical displacements in the piezo beam.
PLNSOL,U,Z
FINISH ! Exit active processor