【寻找】耦合应力求助！

hanhailing

我最近做了T型接头的焊接，温度场和应力场做了之后，现在发现应力值很小，不是预料的值，我不知道什么错了，谢谢大家，我在线等待了！
  
fini
/clear
/filn,therm2
/PREP7   
/COM,  Structural   
/COM,  Thermal   
ET,1,MESH200
!*   
KEYOPT,1,1,6
KEYOPT,1,2,0
!*   
ET,2,SOLID70
K,1,,0.05,,  
K,2,,0.05,0.006,
K,3,,-0.05,0.006,   
K,4,,-0.05,,
K,5,,-0.003,0.006,   
K,6,,0.005,0.006,   
K,7,,0.0075,0.006,   
K,8,,-0.003,0.007,   
K,9,,-0.002,0.007,  
K,10,,0.002,0.0098,  
K,11,,0.003,0.0105,  
K,12,,0.003,0.057,   
K,13,,-0.003,0.057,  
K,14,,-0.002,0.006,  
K,15,,-0.003,,   
K,16,,-0.002,,   
K,17,,0.005,,   
K,18,,0.0075,,
a,1,2,7,18  
a,6,7,18,17
a,6,17,16,14
a,5,14,16,15
a,3,4,15,5
a,8,9,10,6,14,5
a,10,11,7,6
a,8,9,10,11,12,13
k,20,0.03,0.05,0.006
lesize,1,,,1
lesize,2,,,10
lesize,3,,,1
lesize,4,,,10
lesize,5,,,2
lesize,6,,,2
lesize,7,,,1
lesize,8,,,6
lesize,9,,,1
lesize,10,,,6
lesize,11,,,2
lesize,12,,,2
lesize,13,,,1
lesize,14,,,1
lesize,15,,,14
lesize,16,,,14
lesize,17,,,2
lesize,18,,,4
lesize,19,,,6
lesize,20,,,2
lesize,21,,,2
lesize,22,,,6
lesize,23,,,14
lesize,24,,,2
lesize,25,,,14
l,2,20,15
amesh,all
VDRAG,all, , , , , ,      26   
NUMMRG,all, , , ,LOW
  
MPTEMP,,,,,,,,   
MPTEMP,1,0   
MPTEMP,2,100
MPTEMP,3,200
MPTEMP,4,300
MPTEMP,5,400
MPTEMP,6,500
MPTEMP,7,1200   
MPTEMP,8,2500   
MPDATA,EX,1,,2.02e11
MPDATA,EX,1,,1.87e11
MPDATA,EX,1,,1.79e11
MPDATA,EX,1,,1.70e11
MPDATA,EX,1,,1.61e11
MPDATA,EX,1,,1.37e11
MPDATA,EX,1,,0.05e11
MPDATA,EX,1,,0.05e11
MPDATA,PRXY,1,,0.28  
MPDATA,PRXY,1,,0.28  
MPDATA,PRXY,1,,0.3   
MPDATA,PRXY,1,,0.3   
MPDATA,PRXY,1,,0.3   
MPDATA,PRXY,1,,0.35  
MPDATA,PRXY,1,,0.4   
MPDATA,PRXY,1,,0.5   
TB,BKIN,1,5,2,1  
TBTEMP,0
TBDATA,,305e6,2.5e8,,,,  
TBTEMP,200   
TBDATA,,259e6,2.2e8,,,,  
TBTEMP,300   
TBDATA,,200e6,1.75e8,,,,
TBTEMP,1200  
TBDATA,,3e6,1.5e8,,,,   
TBTEMP,2500  
TBDATA,,3e6,0.12e8,,,,   
MPTEMP,,,,,,,,   
MPTEMP,1,0   
MPTEMP,2,100
MPTEMP,3,200
MPTEMP,4,300
MPTEMP,5,400
MPTEMP,6,500
MPTEMP,7,1200   
MPTEMP,8,2500   
MPDATA,DENS,1,,7820  
MPDATA,DENS,1,,7800  
MPDATA,DENS,1,,7800  
MPDATA,DENS,1,,7800  
MPDATA,DENS,1,,7800  
MPDATA,DENS,1,,7800  
MPDATA,DENS,1,,7800  
MPDATA,DENS,1,,7800  
MPTEMP,,,,,,,,   
MPTEMP,1,0   
MPTEMP,2,100
MPTEMP,3,200
MPTEMP,4,300
MPTEMP,5,400
MPTEMP,6,500
MPTEMP,7,1200   
MPTEMP,8,2500   
UIMP,1,REFT,,,   
MPDE,ALPX,1  
MPDE,ALPY,1  
MPDE,ALPZ,1  
MPDATA,ALPX,1,,11.0e-6   
MPDATA,ALPX,1,,11.16e-6  
MPDATA,ALPX,1,,12.12e-6  
MPDATA,ALPX,1,,12.78e-6  
MPDATA,ALPX,1,,13.83e-6  
MPDATA,ALPX,1,,13.93e-6  
MPDATA,ALPX,1,,13.16e-6  
MPDATA,ALPX,1,,13.16e-6  
MPTEMP,,,,,,,,   
MPTEMP,1,0   
MPTEMP,2,100
MPTEMP,3,200
MPTEMP,4,300
MPTEMP,5,400
MPTEMP,6,500
MPTEMP,7,1200   
MPTEMP,8,2500   
MPDE,KXX,1   
MPDE,KYY,1   
MPDE,KZZ,1   
MPDATA,KXX,1,,52
MPDATA,KXX,1,,50.7   
MPDATA,KXX,1,,48.6   
MPDATA,KXX,1,,46.1   
MPDATA,KXX,1,,42.3   
MPDATA,KXX,1,,38.9   
MPDATA,KXX,1,,30
MPDATA,KXX,1,,30
MPTEMP,,,,,,,,   
MPTEMP,1,0   
MPTEMP,2,100
MPTEMP,3,200
MPTEMP,4,300
MPTEMP,5,400
MPTEMP,6,500
MPTEMP,7,1200   
MPTEMP,8,2500   
MPDATA,C,1,,450  
MPDATA,C,1,,469  
MPDATA,C,1,,481  
MPDATA,C,1,,500  
MPDATA,C,1,,536  
MPDATA,C,1,,569  
MPDATA,C,1,,700  
MPDATA,C,1,,700
  
/solu
  
!设定参考温度
tunif,20
!在所有外表面施加对流载荷
asel,s,ext
sfa,all,,conv,30,20
allsel
  
!把焊缝区的单元死掉
vsel,s,volu,,6
nslv,r,1
nsel,r,loc,x,0.2,0
esln,r,1,all
estif,1e-20
ekill,all
allsel
vsel,s,volu,,7
eslv,r,1
nsel,r,loc,x,0.2,0
estif,1e-20
ekill,all
allsel
  
*do,i,1,15
!激活单元
vsel,s,volu,,6
nslv,r,1
nsel,r,loc,x,0.002*i,0.002*(i-1)
esln,r,1,all
ealive,all
bfe,all,hgen,,6.88e10
allsel
  
time,0.2*i
antype,4
trnopt,full
nropt,full!设定N-R选项
kbc,1
nsubst,50,100,20
autots,on
lnsrch,on
outres,all,last
solve
bfedele,all,hgen
*enddo                                                                    
allsel
  
*do,i,16,30
vsel,s,volu,,7
nslv,r,1
nsel,r,loc,x,0.002*(i-15),0.002*(i-16)
esln,r,1,all
ealive,all
bfe,all,hgen,,6.88e10
allsel
  
time,0.2*i
antype,4
trnopt,full
nropt,full!设定N-R选项
kbc,1
nsubst,50,100,20
autots,on
lnsrch,on
outres,all,last
solve
bfedele,all,hgen
*enddo
  
!冷却过程
time,3606
antype,4
trnopt,full
nropt,full!设定N-R选项
kbc,1
nsubst,50,100,20
autos,on
lnsrch,on
outres,all,-5
solve
  
allsel
/prep7
etchg,tts
finish
  
/solu
antype,4
tref,20
ldread,temp,last,,,,,rth
time,3606
kbc,0
cnvtol,f,,,,0.02
nropt,modi
nlgeom,on
timint,on
nsubst,100,200,50
autos,on
lnsrch,on
eqslv,front
outres,all,10
solve

ainite

我跑了一下，MAX von miss stress有二百多MPa，不小了呀。你说的应力小是指什么？

hanhailing

我说的那个值小是我取了其中一些点，我是取上表面的横截面方向的x方向的点，那些点的值很小，请看看我的附图，焊缝的值为压应力的，别的地方是拉应力，这和实际相反的。冷却之后的应力，焊缝的应该是拉应力的，别的地方是压应力。谢谢了

hanhailing

那个是200多的那个应力值的图，这个是应力的横截面的值

chenguanci

hanhailing的应力计算中，为什么只加载了最后一步的温度值？理论上冷却到最后是常温。