很简单的程序，但是为什么就是不收敛呢？

abcdefg987

热电耦合，计算电流密度。
就是不收敛，怎么办呢？
加过CNVTOL,AMPS,,,,-1
这样确实可以收敛，但是据说这样的结果不可靠。
请高人指点。
轴对称，热电耦合。气体高温下。模拟电弧。

Finish
/clear
/PREP7  
ET,1,PLANE67,,,1
!First process.This process is thermal-electric coupled calculation.
!Material properity.Material 1 is the argon,material 3 is tungsten electrobe.
MPTEMP,1,273,2500,5000,7500,10000,12500
MPTEMP,7,15000,17500,20000
MPDATA,DENS,1,1,1.67,0.2,0.1,0.07,0.04,0.03
MPDATA,DENS,1,7,0.02,0.015,0.014
MPDATA,KXX,1,1,0,0.1,0.2,0.3,0.6,1.6
MPDATA,KXX,1,7,2.4,2.0,2.2  
MPDATA,RSVX,1,1,1000,100,1,1.3e-3,3.3e-4,1.6e-4
MPDATA,RSVX,1,7,1.2e-4,9.8e-5,8.5e-5
MPDATA,C,1,1,521,521,521,600,1250,6000
MPDATA,C,1,7,10000,4000,2500
MPDATA,DENS,3,,19350
MPDATA,RSVX,3,,0.0000000528
MPDATA,KXX,3,,173
K,1,0,0,0,  
k,2,0.01,0,0,  
K,3,0.0002,0,0,
K,4,0.0016,0,0,
K,5,0,0.005,0,  
K,6,0.0002,0.005,0,
K,7,0,0.005+0.0014*sqrt(3),0,   
K,8,0.0016,0.005+0.0014*sqrt(3),0,  
K,9,0.01,0.005+0.0014*sqrt(3),0,
K,10,0.0016,0.005,0,
K,11,0.01,0.005,0,  
A,5,6,8,7   
A,1,3,6,5   
A,3,4,10,6     
A,6,10,8  
A,8,9,11,10   
A,10,11,2,4   
LGLUE,ALL   
AGLUE,ALL
ASEL,S,AREA,,2,6
AATT,1,,1,0,
ASEL,S,AREA,,1
AATT,3,,1,0,
allsel，all
ESIZE,0.0002,0,
MSHKEY,1  
AMESH,ALL
/PNUM,KP,1  
/PNUM,AREA,1
APLOT
FINISH  
/SOL
TUNIF,10000, !uniform temperature
DL,12,,TEMP,1000,0
LSEL,S,LINE,,1,3   !the top of the argon
DL,ALL,,TEMP,3000,0
LSEL,S,LOC,Y,0     !the surface of the tungsten electrobe.
DL,ALL,,TEMP,5000,0
DL,ALL,,VOLT,0     !the bottom of the argon(the top of the workpiece,here the workpiece is neglected)
LSEL,S,LINE,,3
NSLL,S,1           !the top of the tunsten electrobe
F,ALL,AMPS,-160    !Here is the difficulity, because I can't make the direction of current from top to bottom.
ALLSEL,ALL
SOLVE
FINISH

woodcopper

有一关键的问题你可能忽略了，你的计算没有辐射！

如果热量只能急剧上升而不能找到相对的平衡点可能就不会收敛了！