模仿的论坛上的例子没有得到应有的结果，请各位大侠看看！

ps3

这个例子是2007年"6个不错的例子---------程序完整详细"这个帖子中第3个例子的实现，其中建模部分是参考“求助压电悬臂梁的静态仿真问题，不知为什么没有结果”这个帖子中斑竹老师的代码，但是最后谐响应分析的结果与文档中给出的结构不一样，还请斑竹老师及各位大侠看看，谢谢！
/FILENAME,PZT-beam
! 定义分析文件名
/TITLE,Modal and static 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   
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,            ! Model the beam
/PREP7
BLC4,0,0, LBEAM, WBEAM, TBEAM
BLC4,0,0, L_PTB, WBEAM, TBEAM
BLC4,0,0, LBEAM, W_PTB, TBEAM
BLC4,0,0, L_PZT, WBEAM, TBEAM
BLC4,0,0, LBEAM, W_PZT, TBEAM
BLC4,0,0, L_PTT, WBEAM, TBEAM
BLC4,0,0, LBEAM, W_PTT, TBEAM
BLC4,0,0, L_PZT,W_PZT, TBEAM+ T_PZT
BLC4,0,0, L_PTT,W_PZT, TBEAM+ T_PZT
BLC4,0,0, L_PZT, W_PTT, TBEAM+ T_PZT
BTOL,1e-006
VOVLAP ,ALL
/VIEW,1,1,1,1      ! 变换视角
/AUTO,1            ! 自动适应窗口大小
/TRIAD,OFF
VPLOT              ! 显示体

/COM,              ! 对于三种材料网格剖分

/COM,-------------------- Mesh PZT volumes
VSEL,S,LOC,Z,tbeam,tbeam+t_pzt     ! Select volumes by Z coordinate location (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                     ! Mesh si
VSEL,S,LOC,Z,0,tbeam     ! Select Si volumes
TYPE,2
MAT,2
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 lower electrode areas
ASEL,R,LOC,X,0, L_PTB
ASEL,R,LOC,Y,0,W_PTB
REAL,1                    !Real constant set 1 (bottom Pt electrode thickness)
AMESH,ALL                 ! Mesh all selected areas
NSLA,S,1                  ! Select nodes based on selected areas
!!!!!!!!!!!!这是自己加的
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

/COM,-------------------- Mesh top Pt electrode and define component by nodes
ASEL,S,LOC,Z,tbeam+t_PZT       ! Select upper electrode areas
ASEL,R,LOC,X,0, L_PTT
ASEL,R,LOC,Y,0,W_PTT
REAL,2        ! Real constant set 1 (top Pt electrode thickness)
AMESH,ALL     ! Mesh all selected areas
NSLA,S,1        ! Select nodes based on selected areas
!!!!!!!!!!!!这是自己加的
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

/SOLU                      ! Enter solution processor
ANTYP,HARM                 ! Harmonic analysis type
HARFRQ,0.310E+06,0.314E+06 ! Frequency range for analysis
NSUBST,10                  ! Number of steps to calculate
KBC,1                      ! Step loads (no ramp)

D,bot_elec,VOLT,0.0        ! Assign zero potential to a node of top electrode
D,top_elec,VOLT,10.0       ! Assign cyclic potential of 10 V to 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,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


/POST26                    ! Enter time-history post-processor
NSEL,S,LOC,Y,0             ! Select nodes with coordinates Y=0
NSEL,R,LOC,Z,0             ! Reselect coordinates with Z=0
NSEL,R,LOC,X,lbeam         ! Reselect coordinates with X=lbeam
*GET,ntip,NODE,,NUM,MIN    ! Get number of node at beam tip (selected node)
NSOL,2,ntip,U,Z,tip_uz     ! Store node ntip vert. displ. in variable tip_uz
NSEL,ALL                   ! Select all nodes
WPCSYS                     ! Align work-plane with global coordinate system
PRVAR,2                    ! List data for tip_uz variable
!PLVAR,2                    ! Plot displacements as a function of frequency
FINISH                     ! Exit active processor

上面代码运行的结果


文档中给出的结果


ps.是新手，从模仿开始啊！还请各位大大多指导

shenda1304

第二幅图中振动的平衡位置是0.4，正负最大幅值与平衡位置之差都是1.2哦，感觉这个是围绕平衡位置上下振动的，而楼主做的结果只是在一个方向振动，回答不了问题只能帮忙顶一下啦，希望路过的大侠能帮你哈

ps3

刚在help里面看到谐响应分析中有这句话“Damping in some form should be specified; otherwise, the response will be infinity at the resonant frequencies.”必须指定某种形式的阻尼，否则在共振频率处的响应将无限大。是不是这个的问题啊，有看到有人用mp,dmpr,1,0.006哦。

ps3

加了常阻尼mp,dmpr,1,0.006还是不行，结果如下


请路过的大虾们指导一下，谢谢啦！

ps3

hy1966版主曾经说过：“谐分析：必须输入阻尼，以避免谐振响应出现无穷大。一般从α-阻尼、β-阻尼和阻尼率中选取，恒阻尼率最常用。”但是文章中没有加阻尼也没有出现无穷大，是不是有的结构会出现无穷大而有的结构不会出现？这里的问题应该不是出在阻尼上，肯定是其他地方出错了？