ansys关于槽钢公式计算和有限元计算结果的差异问题
小弟最近在琢磨槽钢的简单计算,发现一个问题,就是理论计算上的挠度和有限元的结果(beam和solid单元分别都使用了)一直对照不上,基本上是差一倍的偏差。但是用对称的型钢,比如方钢,工字钢两者计算就没这个问题,不知是什么原因。以下是公式计算和有限元计算结果,载荷就是型钢的自重,最终结果要显示截面的云图(所以beam3,beam4就不考虑使用了)。有懂的虫友,请赐教。
!!!!***************上梁采用18#a槽钢(梁单元计算)*****************
finish
/clear
/prep7
et,1,188
mp,ex,1,2.0e11
mp,dens,1,7800
mp,prxy,1,0.3
SECTYPE, 1, BEAM, CHAN, , 0
SECOFFSET, CENT
SECDATA,68/1000,68/1000,180/1000,10.5/1000,10.5/1000,7/1000,0,0,0,0
k,
k,2,2330/1000
k,3,,200/1000
k,4,2330/1000,-200/1000
l,1,2
wpoff,0.555
wprot,,,-90
lsbw,all
wpoff,,,-1.22
lsbw,all
kwpave,1,2
lsbw,all
NUMMRG,ALL
NUMCMP,ALL
/eshape,1
/VIEW,1,1,1,1
/ANG,1
/REP,FAS
LESIZE,1, , ,20, , , , ,1
LESIZE,2, , ,20, , , , ,1
LESIZE,3, , ,30, , , , ,1
LESIZE,4, , ,30, , , , ,1
latt,1,,1,,3,,1
lmesh,1
latt,1,,1,,4,,1
lmesh,2
latt,1,,1,,4,,1
lmesh,3
latt,1,,1,,3,,1
lmesh,4
eplot
/solu
!FK,2,FY,14500
acel,0,9.8,0
DK,1, , , ,0,ALL, , , , , ,
!DK,2, , , ,0,UY,UZ,ROTX,ROTY,ROTZ, ,
alls
/solu
eqslv,PCG,1e-3 !选择PCG算法
msave,on
solve
/post1
/dsacle,all,1
PLNSOL, U,Y, 0,1.0
!!!!***************上梁采用18#a槽钢(实体单元计算)*****************
finish
/clear
/prep7
et,1,95
mp,ex,1,2e11
mp,dens,1,7800
mp,prxy,1,0.3
BLOCK,0,2.33,90/1000,-90/1000,63/2/1000,-63/2/1000,
BLOCK,0,2.33,90/1000-10.5/1000,-90/1000+10.5/1000,63/2/1000,-63/2/1000+7/1000,
vsbv,1,2
aesize,all,0.025/2
vsweep,all
/solu
asel,,,,15
nsla,s
d,all,all
alls
wpcsys,-1,0
csys,4
KWPAVE,3,4,6,7
nsel,s,loc,x,0,0
*GET,nn,NODE,,COUNT
F,ALL,FY,14500/nn
alls
solve
/post1
/dscale,all,1
PLNSOL, U,Y, 0,1.0
finish
/clear
/prep7
et,1,95
mp,ex,1,2e11
mp,dens,1,7800
mp,prxy,1,0.3
BLOCK,0,2.33,90/1000,-90/1000,63/2/1000,-63/2/1000,
BLOCK,0,2.33,90/1000-10.5/1000,-90/1000+10.5/1000,63/2/1000,-63/2/1000+7/1000,
vsbv,1,2
aesize,all,0.025/2
vsweep,all
alls
et,2,MASS21
r,2,0,0,0, , , ,
wpcsys,-1,0
csys,4
KWPAVE,3,4,6,7
n,1e6,0,0,0 !定义质量单元节点位置
TYPE,2
REAL,2
E,1e6
nsel,s,loc,x,0,0
CM,NP,node
NSEL,A,NODE,,1e6
CERIG,1e6,ALL,UXYZ
alls
/solu
asel,,,,15
nsla,s
d,all,all
alls
acel,0,9.8,0
!F,1e6,FY,14500
alls
solve
/post1
/dscale,all,1
PLNSOL, U,Y, 0,1.0
QQ截图20180802093608.png 返回小木虫查看更多
BLOCK,0,2.33,90/1000,-90/1000,63/2/1000,-63/2/1000,更正为
BLOCK,0,2.33,90/1000,-90/1000,68/2/1000,-68/2/1000,
BLOCK,0,2.33,90/1000-10.5/1000,-90/1000+10.5/1000,63/2/1000,-63/2/1000+7/1000, 更正为
BLOCK,0,2.33,90/1000-10.5/1000,-90/1000+10.5/1000,68/2/1000,-68/2/1000+7/1000,
实体单元分析更正为:
finish
/clear
/prep7
et,1,95
mp,ex,1,2e11
mp,dens,1,7800
mp,prxy,1,0.3
BLOCK,0,2.33,90/1000,-90/1000,68/2/1000,-68/2/1000,
BLOCK,0,2.33,90/1000-10.5/1000,-90/1000+10.5/1000,68/2/1000,-68/2/1000+7/1000,
vsbv,1,2
aesize,all,0.025/2
vsweep,all
/solu
asel,,,,15
nsla,s
d,all,all
alls
acel,0,9.8,0
alls
solve
/post1
/DSCALE,ALL,1.0
PLNSOL, U,Y, 0,1.0,