最近,我在书上看到过一个例题,是关于轴的扭转分析,换了另外一种建摸方式,结果就相差一倍,问题也没检查出来,哪位大侠能否指点下。
原题条件为对一个直径为50mm,长度为120mm得实心轴在轴的两端施加扭矩1.5e3 N.m。求轴的最大剪应力。
例题程序为
/PREP7
ET,1,PLANE42
ET,2,SOLID45
MP,EX,1,2.08e11
MP,PRXY,1,0.3
rectng,0,0.025,0,0.12
lesize,1,,,4
lesize,2,,,8
mshape,0
mshkey,1
amesh,1
extopt,esize,6
extopt,aclear,1
vrotat,1,,,,,,1,4,360
wprot,0,90
cswpla,11,1,1,1
nsel,s,loc,x,0.025
nrotat,all
/solu
d,all,ux
nsel,r,loc,z,-0.12
f,all,fy,2500
allsel,all
da,2,all
da,6,all
da,10,all
da,14,all
SOLVE
FINISH
/POST1
!*
RSYS,11
AVPRIN,0,0
AVRES,2,
/EFACET,1
LAYER,0
PLESOL, S,XY, 0,1.0
所得结果为60.15
而我换种模型后所得的结果为他的两倍,
源程序如下:
/prep7
et,1,solid45
mp,ex,1,2.08e11
mp,prxy,1,0.3
CYL4,0,0,0.025, , , ,0.12
wprota,,,90
vsbw,1
wprota,,90
vsbw,all
lsel,s,,,1,8,1
LESIZE,all, , ,5, , , , ,1
lsel,s,,,9,10,1
lsel,a,,,13,14,1
lesize,all,,,20,,,,,1
mshape,0
mshkey,2
vmesh,all
nummrg,all
numcmp,all
WPCSYS,-1,0
cswpla,11,1,1,1
nsel,s,loc,x,0.025
nrotat,all
d,all,ux
nsel,r,loc,z,0.12
f,all,fy,2500
allsel,all
nsel,s,loc,z,0,0
d,all,all
/solu
allsel,all
solve
/post1
RSYS,11
AVPRIN,0,0
AVRES,2,
/EFACET,1
LAYER,0
PLESOL, S,XY, 0,1.0 |