谐响应分析中可否分析温度载荷
各位高手，我在作一个谐响应分析，就是分析不同温度下的振动频率的变化。我采用的压电材料，施加的是初始温度还有热膨胀系数，但是计算过后没有什么太多的变化，甚至跟预想的结果相反，能否得到高手的指点。 你具体是怎么做的？把命令流贴出来看一下 我一开始是加了初始温度，温度从0到1000不等。我发一个是初始温度为100的吧。然后进行静力分析。/batch,list
/prep7
/title,Transient and harmonic analyses of a piezoelectric circuit
/nopr
!
! Set up the model for the piezoelectric element
!
! Material properties for PZT-4
!
mp,DENS,1,7700 ! Density, kg/m**3
et,1,SOLID226,1001 ! 3-D coupled-field brick, piezo option
tb,DPER,1 ! Relative permittivity at constant strain
tbdata,1,729,635,729
! - Alternative input of permittivity if used with SOLID5
! mp,PERX,1,729
! mp,PERY,1,635
! mp,PERZ,1,729
!
tb,ANEL,1 ! Anisotropic elastic stiffness, N/m^2
tbdata,1,13.9E10,7.43E10,7.78E10! c11,c13,c12
tbdata,7,11.5E10,7.43E10 ! c33,c13
tbdata,12,13.9E10 ! c11
tbdata,16,3.06E10 ! c44
tbdata,19,2.56E10 ! c44
tbdata,21,2.56E10 ! c66
tb,PIEZ,1 ! Piezoelectric stress coefficients, C/m^2
tbdata,3,-5.2 ! e31
tbdata,6,15.1 ! e33
tbdata,9,-5.2 ! e31
tbdata,11,12.7 ! e15
tbdata,16,12.7 ! e15
MPTEMP,,,,,,,,
MPTEMP,1,0
UIMP,1,REFT,,,
MPDATA,ALPX,1,,3e-6
MPTEMP,,,,,,,,
MPTEMP,1,0
MPDATA,KXX,1,,2.1
MPTEMP,,,,,,,,
MPTEMP,1,0
MPDATA,C,1,,420
!
! material properity for steel( mass block)
et,2,solid45
mp,nuxy,2,0.3
mp,ex,2,206e9
mp,dens,2,7895
MPTEMP,,,,,,,,
MPTEMP,1,0
UIMP,1,REFT,,,
MPDATA,ALPX,2,,1.2e-5
!************* Define a piezoelectric cube (H = 1 mm)
!
r=0.005
t=0.001
H = 0.004 ! Transducer size, m
CYL4, , ,r, , , ,t ! Define volume
/REPLO
WPSTYLE,,,,,,,,1
CSYS,4 ! buid the mass block
wpoff,,,0.001
CYL4, , ,r, , , ,H
VGLUE,all
!
type,2
mat, 2
esize,0,6
vsweep,3
type,1
mat,1
esize,0,6
vsweep,1
!
csys,0
nsel,s,loc,z,0 ! Define bottom electrode
cp,1,volt,all
*get,n_bot,node,0,num,min ! Get master node on bottom electrode
nsel,s,loc,z,t ! Define top electrode
cp,2,volt,all
*get,n_top,node,0,num,min ! Get master node on top electrode
nsel,s,loc,z,0 ! Impose displacement constraints
d,all,uz,0.001
d,n_bot,volt,0 ! Ground bottom electrode
nsel,all
tunif,100
fini
!
/solu
antype,static
nlgeom,on
sstif,on
nsubst,10
lnsrch,on
allse
solve
save,10,db
fini
!
fini
!
/solu
antype,modal ! Modal analysis
nmodes = 9 ! Number of modes
MODOPT,LANB,9,1000,300000, ,OFF ! Block Lanczos solver
mxpand,nmodes,,,yes ! Calculate element results and reaction forces
solve ! Solve for resonance frequency
fini
/post1
*get,F1,mode,1,freq
*get,F2,mode,2,freq
*get,F3,mode,3,freq
*get,F4,mode,4,freq
*get,F5,mode,5,freq
*get,F6,mode,6,freq
*get,F7,mode,7,freq
*get,F8,mode,8,freq
*get,F9,mode,9,freq
fini
save,11,db
!
/solu
antype,3 ! 谐响应分析
HARFRQ,0,300000,!*********给定求解频率范围
NSUBST,100, !*********设定求解载荷步数
KBC,1
!*
DMPRAT,0.002, !*********设定相对阻尼系数
SOLVE
FINISH !**求解结束，进入时间历程后处理器
save,12,db
!
!
/POST26
/UI,COLL,1
NUMVAR,200
SOLU,191,NCMIT
STORE,MERGE
PLCPLX,0
PRCPLX,1
FILLDATA,191,,,,1,1
REALVAR,191,191
!*
NSOL,2,n_top,VOLT,, VOLT_2 !**********提取22号节点（耦合最小编号的点）电势，定义成2号参数
STORE,MERGE
PLCPLX,2
PRCPLX,0
FILLDATA,192,,,,0,0
FILLDATA,193,,,,1,0
FILLDATA,194,,,,-1,0
FILLDATA,195,,,,1,1
VARNAME,195,NSET
!
! Name: a
! ID:3
! Function: 0.00628*6.28*{FREQ}*{FREQ} !************加速度a的计算式
FILLDATA,199,,,,0.00628,0
REALVAR,199,199
FILLDATA,198,,,,6.28,0
REALVAR,198,198
PROD,200,198,199
PROD,199,200,1
PROD,3,199,1,,a
!
STORE,MERGE
FILLDATA,192,,,,0,0
FILLDATA,193,,,,1,0
FILLDATA,194,,,,-1,0
FILLDATA,195,,,,1,1
VARNAME,195,NSET
!
! Name: Ma
! ID:4
! Function: {VOLT_2}/{a} !***********求出加速度灵敏度（电压型）
QUOT,4,2,3,,Ma
!
STORE,MERGE
XVAR,1
PLVAR,4, !*********画出加速度灵敏度的频响曲线
fini
!
! 由于材料本身的性能随温度讲发生变化，但是在求解结果分析时，却发现与实际相反的结果。我想问问谐响应是不是可以考虑温度的特性呢。还有固有频率会随着温度增加还是减少呢。请高手指点。谢谢了。 固有频率特性是和材料的刚度相关的；
如果材料的刚度是随温度变化的，那么就可以考虑这一影响；
因此，分析的时候也要定义材料的非线性特性随温度变化的曲线； 果然高手多的 但是， 谐响应是不考虑非线性的。这样改如何考虑呢？
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