求解答疑问，关于ansys做热结构的简单焊接残余应力分析

火云

本人刚学这个，刚开始选用简单模型，在热分析后进行结构分析，总是提醒单元变形过大，导致没有结果（只有一个荷载步）。求大神解释下，看看问题所在。

FINISH
/CLEAR,NOSTART
/filname,weld_plane
/title,test of temperature field
/prep7  
/units,si   
!!element type  
et,1,solid70
keyopt,1,7,0
!keyopt,1,1,0
mptemp,1,20,100,500,800,1000,1500
mpdata,kxx,1,1,34
mpdata,dens,1,1,7860
mpdata,c,1,1,600
t=4.5/1000
b=30/1000
l=100/1000
bweld=2/1000
block,0,bweld,-b/2,b/2,0,t
cm,v_weld,volu
cmsel,u,v_weld
block,bweld,bweld+l/4,-b/2,b/2,0,t
cm,v_p1,volu
cmsel,u,v_p1
block,bweld+l/4,bweld+l,-b/2,b/2,0,t
cm,v_p2,volu
allsel
!==============
!划分单元网格
*set,nt_weld,4
*set,nb_weld,20
*set,nl_weld,2
*set,nt_pv2,2
*set,nb_pv2,10
*set,nl_pv2,20
lsel,s,loc,x,0
lsel,a,loc,x,bweld
lsel,r,length,,t
lesize,all,,,nt_weld
lsel,s,loc,x,0
lsel,a,loc,x,bweld
lsel,r,length,,b
lesize,all,,,nb_weld
lsel,s,length,,bweld
lesize,all,,,nl_weld
lsel,s,loc,x,bweld+l/4
lsel,a,loc,x,bweld+l
lsel,r,length,,t
lesize,all,,,nt_pv2
lsel,s,loc,x,bweld+l/4
lsel,a,loc,x,bweld+l
lsel,r,length,,b
lesize,all,,,nb_pv2
lsel,s,length,,3*l/4
lesize,all,,,nl_pv2
allsel
lsel,s,length,,l/4
lesize,all,,,7
type,1
mat,1
allsel
cmsel,s,v_weld
cmsel,a,v_p2
vmesh,all
allsel
mshape,1
vmesh,v_p1
nummrg,all
numcmp,all
!对焊缝分段
allsel
cmsel,s,v_weld
eslv,s
cm,el_weld,elem
nsle,s
cm,no_weld,node
allsel
*set,n,
*do,j,1,nb_weld
cmsel,s,no_weld
nsel,r,loc,y,-b/2+(j-1)*b/nb_weld,-b/2+j*b/nb_weld
cm,no_weld%j%,node
esln,s,1
cm,el_weld%j%,elem
*enddo
allsel
!=================
!求解
/solu
antype,4
trnopt,full
lumpm,0      !使用单元本身的质量矩阵公式（default）
autots,on
kbc,1
outres,all,all
tintp,0.005     !瞬态积分常数
timint,1,struc
timint,1,therm
timint,0,mag
timint,0,elect
tunif,20        !!!inputs initial temperature of all nodes
tref,20         !!!inputs reference temperature of all nodes
ic,all,temp,20
!定义对称边界
nsel,s,loc,x,0
sf,all,hflux,0
alls
!对流边界条件
nsel,s,loc,x,bweld+l
nsel,a,loc,y,-b/2
nsel,a,loc,y,b/2
nsel,a,loc,z,0
nsel,a,loc,z,t
sf,all,conv,13,20
allsel
!温度边界条件
nsel,s,loc,x,bweld+l
d,all,temp,20
allsel
!===================
!焊接过程求解
*set,dt,0.001
*set,t0,5
*set,t,0
time,0
!cmsel,s,el_weld
!ekill,all
*do,i,1,nb_weld
alls
   t=t+t0
   time,t
   nsubst,1
   !cmsel,s,el_weld
   !ealive,all   
   cmsel,s,no_weld%i%
   d,all,temp,1500
   !bf,all,hgen,2.8e9
   allsel
   solve
alls
   t=t+dt
   time,t
   cmsel,s,no_weld%i%
   ddele,all,temp
   !bfdele,all,hgen
   alls
   solve
alls
   t=t+t0
   time,t
   alls
   solve
*enddo
   
*do,j,1,6
   alls
   nsubst,5
   t=t+100
   time,t
   solve
*enddo


!===============================
!the analysis of residual stress
!===============================
/prep7
alls
etchg,tts   !Changes element types to their corresponding types
!Thermal to Structural
mptemp,1,20,100,500,800,1000,1500
mpdata,ex,1,1,2.1e11,2.01e11,1.75e11,1.01e11,0.065e11,0.01e11
mpdata,alpx,1,1,14.8
mp,prxy,1,0.3
tb,biso,1,6,2
tbtemp,20
tbdata,,310e6,0
tbtemp,100
tbdata,,260e6,0
tbtemp,500
tbdata,,203e6,0
tbtemp,800
tbdata,,70e6,0
tbtemp,1000
tbdata,,8e6,0
tbtemp,1500
tbdata,,1e6,0
tbplot
!施加边界约束define the boundary condition in structural analysis
nsel,s,loc,x,0
dsym,symm,x
alls
nsel,s,loc,x,bweld+l
d,all,ux
d,all,uy
d,all,uz

/solu
tref,20
alls
antype,4
nlgeom,1
autots,on
kbc,0    !!!Specifies stepped or ramped loading within a load step
lnsrch,1
time,0
toffst,273.15
outres,all,all
*do,i,1,nb_weld
t=0
alls
   t=t+t0
   time,t
   ldread,temp,,,t,,'weld_plane','rth'
   solve
   
   t=t+dt
   time,t
   ldread,temp,,,t,,'weld_plane','rth'
   solve
   
   t=t+t0
   time,t
   ldread,temp,,,t,,'weld_plane','rth'
   solve
*enddo
*do,j,1,6
   alls
   t=t+100
   nsubst,5
   time,t  
   ldread,temp,,,t,,'weld_plane','rth'
   solve
*enddo

火云

自己顶一个，寻求帮助ing

火云

寻求帮助ing

火云

这论坛这么冷清啊，顶下，等待帮助啊

火云

还得靠自己，初步解决。某个参数定义少了个系数

xtuwyb

哪个参数啊？楼主是做的是移动热源不？

bqc

这个不是移动热源，是加的初始温度，1500
但是这个d,all,temp,1500为什么要写在循环里？

火云

bqc 发表于 2012-11-8 02:26
这个不是移动热源，是加的初始温度，1500
但是这个d,all,temp,1500为什么要写在循环里？ ...

我试的是分段施加温度荷载看看效果，真真的移动热源应该计算比较复杂耗时吧