求助ANSYS随机振动功率谱密度分析

guess641

近期在做一个随机振动功率谱密度的仿真（在线等）
参考了一些教程后，编了一段代码，可是得出的VON-MIZE应力全部是零，无奈试了很多办法，可依旧无法解决，向各位高手请教
附求解部分源代码：

/SOLU
ANTYPE,2
ALLSEL,ALL
MODOPT,LANB,10,0,2000,,OFF
EQSLV,SPARSE
MXPAND,10,,,0
PSTRES,1   !前面有预应力的计算
SAVE
SOLVE
FINISH

/SOLU
NSEL,R,LOC,X,L   !先限制一个点的自由度以便后面加载
NSEL,R,LOC,Y,d1/2
D,ALL,UY
ALLSEL,ALL
ANTYPE,8
SPOPT,PSD,10,1
PSDUNIT,1,ACCG,20.0
PSDFRQ,1,,10,50,100,200,300
PSDFRQ,1,,316.22777,398.10717,501.18723,630.95734,794.32823,1000
PSDVAL,1,0.8,0.8,0.8,0.8,0.8
PSDVAL,0.8,0.55604556,0.40409264,0.29366454,0.21341359,0.15509315,0.11271019
NSEL,R,LOC,X,L
NSEL,R,LOC,Y,d1/2
D,ALL,UY,1
ALLSEL,ALL
PFACT,1,BASE,
PSDRES,DISP,ABS
PSDRES,VELO,ABS
PSDRES,ACEL,ABS
SAVE
SOLVE
FINISH

/SOLU
ANTYPE,8
PSDCOM,0.005,10
SAVE
SOLVE
FINISH

/POST1
SET, , ,1, , , ,12,
PLDISP,2
PLNSOL, S,EQV, 0,1.0
FINISH

aircraft

感觉:
/POST1后处理器里的代码有点问题
SET, , ,1, , , ,12,
???
读出第12阶模态的扩展模态解吗?
通过PLDISP,2看振型是吗?
然后再通过PLNSOL,S,EQV来看等效应力云图?
不过前面好象先得读入1thegma解吧,
不使用set,3,1可以吗?

guess641

SET, , ,1, , , ,12,  和set,3,1  效果一样吧
一共十阶模态 SUBSTEP12 正好就是step3

aircraft

没有使用过这样的表示方法,
:@)
不过你既然用的是SET,3,1是读入应力解的话
也能同时读出振型吗?
PLDISP,2也能表达出来吗
?
仔细从头到尾看了遍,
基本的没有多大问题,
不排除谱密度可能有问题,
使用地是重力加速度谱
这里的20.0是怎么得来地?
缺省使用的英寸单位,是386.4,

aircraft

你的意思是:
set,1,11也就是set,2,1了?

guess641

我把这个参数当作加速度功率谱密度的总均方根值了
刚才把程序段重新修改了一下，从新计算了一遍，还是老问题
不过还是非常感谢aircraft抽出时间看了这段代码，给我指出了一些问题
FINISH
/CLEAR
/FILNAM,CONDUIT CONNECTOR
/TITLE,Conduit Connector
/UNITS,SI
/PNUM,KP,1  
/PNUM,LINE,1
/PNUM,AREA,1
/PNUM,VOLU,1


d=4
d1=6.8
d2=9
d3=10.3
d4=7.4
L=21
b1=4.5  !球形宽度±0.1
b2=2    !凸台宽度±0.6
r=6     !球头圆弧半径±0.15
r2=0.3  !圆角半径 ±0.15
EXX=2.07E11   !杨氏模量
PRXY=0.3
*AFUN,DEG   !角度
THETA=30
fixation=b1-r*SIN(THETA) !确定固定位置
dnut=7.5 !预应力作用位置大小
M=12      
T=30     ! M,T用于求出预应力大小
/PREP7
MP,DENS,1,7.8E3
MP,EX,1,EXX
MP,PRXY,1,PRXY

k,99,0,0,0
k,1,0,-d/2,0
k,2,b1,-d2/2,0
k,3,b1,-d3/2,0
k,4,b1+b2,-d3/2,0
k,5,b1+b2,-d1/2,0
k,6,L,-d1/2,0
K,7,L,-d/2,0
K,8,b1,0,0
k,9,10,0,0
LSTR,2,3
LSTR,3,4
LSTR,4,5
LSTR,5,6
LSTR,6,7
LSTR,7,1

LARC,1,2,8,r
lfillt,3,4,r2,12     ! 10点 圆弧中点

k,21,b1+b2*0.75,-d/2,0
k,22,b1+b2*0.75,-d3/2,0
k,23,b1+b2*1.25,-d/2,0
k,24,b1+b2*1.25,-d1/2,0

LSTR,21,22
LSTR,23,24

LCOMB,3,8,0
LCOMB,3,4,0

k,40,b1+b2,-dnut/2,0
LSTR,4,40

LSBL, 3, 4, , DELETE, KEEP

al,7,1,2,4,8,5,6
ASBL,1,9,,,
ASBL,3,10,,,

ET,1,PLANE42
ET,2,SOLID45
ESIZE,0.25,0,       !mesh主要尺寸ESIZE,0.1,0,   
MSHAPE,0,2D
MSHKEY,0
AMESH,4
ESIZE,0.5,0,       !mesh次要尺寸
AMESH,2
AMESH,1

ESIZE,0.6,0,     !mesh体尺寸ESIZE,0.2,0,
VROTAT, 2, 4, 1, , , , 8, 9, 360,2
VSWEEP,1
VSWEEP,2
VSWEEP,3
VSWEEP,4
VSWEEP,5
VSWEEP,6
NUMMEG,ALL,,,
finish

/SOLU
F=T/(0.2*M)
ANTYPE,0
PSTRESS,ON
ALLSEL,ALL
ASEL,S,AREA,,3,20,17
NSLA,S,1
NSEL,R,LOC,X,fixation-b1/6,fixation+b1/6
D,ALL,ALL
/PBC,U,,1
/PBC,F,,1
ALLSEL,ALL
ASEL,S,AREA,,11,26,15
pressarea=3.141593*(d3*d3-dnut*dnut)
SFA, all, , PRES, F/pressarea,
ALLSEL,ALL
SAVE
SOLVE
FINISH

/SOLU
ANTYPE,2
ALLSEL,ALL
MODOPT,LANB,10,0,2000,,OFF
EQSLV,SPARSE
MXPAND,10,,,0
PSTRES,1   !前面有预应力的计算
SAVE
SOLVE
FINISH

/SOLU
NSEL,R,LOC,X,L   !先限制一个点的自由度以便后面加载
NSEL,R,LOC,Y,d1/2
D,ALL,UY
ALLSEL,ALL
ANTYPE,8
SPOPT,PSD,10,1
PSDUNIT,1,ACCG,
PSDFRQ,1,,10,50,100,200,300
PSDFRQ,1,,316.22777,398.10717,501.18723,630.95734,794.32823,1000
PSDVAL,1,0.8,0.8,0.8,0.8,0.8
PSDVAL,0.8,0.55604556,0.40409264,0.29366454,0.21341359,0.15509315,0.11271019
NSEL,R,LOC,X,L
NSEL,R,LOC,Y,d1/2
D,ALL,UY,1
ALLSEL,ALL
PFACT,1,BASE,
PSDRES,DISP,ABS
PSDRES,VELO,ABS
PSDRES,ACEL,ABS
SAVE
SOLVE
FINISH

/SOLU
ANTYPE,8
PSDCOM,0.005,10
SAVE
SOLVE
FINISH

/POST1
set,3,1
PLNSOL, S,EQV, 0,1.0
FINISH