热点耦合温度与理论值差很多，求帮忙
本帖最后由 cryingdevil 于 2012-4-6 18:21 编辑首先，问一下，一个扁圆柱，底面直径0.14m,圆柱高度0.05m,电阻320μΩ（把接触电阻也考虑进去了），我把电阻换成电阻率，是不是直接320e-6*3.14*0.07^2/0.05就行了？
底面通过100A的电流，膜系数取12.5，外界温度25摄氏度，KXX取401
模型很简单，可是温度达到4000度，而且不是中心对称分布，很费解，我刚接触热电耦合，不知道哪里加的不对。
chaos_zzy今天给我讲了验算的方法，我用这个试了一下，焦耳热Q =100^2*320e-6=3.2,总的散热表面积应该是2*3.14*0.07^2+3.14*0.14*0.05=0.053,
最终的温度应该Td=Ta+Q/(A*H)=25+3.2/(12.5*0.053)=29.8啊。。。为什么会到4000呢？
我用GUI做的，刚开始学，命令流还不会，把log文件贴上来大家帮我看看，是不是那个步骤有错
/PREP7
!*
ET,1,SOLID69
!*
!*
MPTEMP,,,,,,,,
MPTEMP,1,0
MPDATA,KXX,1,,401
MPTEMP,,,,,,,,
MPTEMP,1,0
MPDATA,RSVX,1,,9.852e-5
CYL4,0,0,0.07, , , ,0.05
CM,_Y,VOLU
VSEL, , , , 1
CM,_Y1,VOLU
CMSEL,S,_Y
!*
CMSEL,S,_Y1
VATT, 1, , 1, 0
CMSEL,S,_Y
CMDELE,_Y
CMDELE,_Y1
!*
SMRT,6
MSHAPE,1,3D
MSHKEY,0
!*
CM,_Y,VOLU
VSEL, , , , 1
CM,_Y1,VOLU
CHKMSH,'VOLU'
CMSEL,S,_Y
!*
VMESH,_Y1
!*
CMDELE,_Y
CMDELE,_Y1
CMDELE,_Y2
!*
APLOT
/VIEW,1,1,1,1
/ANG,1
/REP,FAST
/PNUM,KP,0
/PNUM,LINE,0
/PNUM,AREA,1
/PNUM,VOLU,0
/PNUM,NODE,0
/PNUM,TABN,0
/PNUM,SVAL,0
/NUMBER,0
!*
/PNUM,ELEM,0
/REPLOT
!*
/USER,1
/VIEW,1,0.761281512784 ,0.260907210786 , -0.593614256612
/ANG, 1, 40.2668576242
/REPLO
/VIEW,1,0.871854605456 ,0.239160003233 ,0.427401497189
/ANG, 1, 20.7576392055
/REPLO
FLST,2,4,5,ORDE,2
FITEM,2,1
FITEM,2,-4
FLST,2,4,5,ORDE,2
FITEM,2,1
FITEM,2,-4
/GO
!*
SFA,P51X,1,CONV,12.5,25
/VIEW,1,0.963490030134 ,0.190913272037 ,0.187720761751
/ANG, 1, 23.9751470168
/REPLO
FLST,2,1,5,ORDE,1
FITEM,2,2
/GO
!*
DA,P51X,VOLT,0
ASEL,S, , , 1
NSLA,S,1
FLST,2,28,1,ORDE,6
FITEM,2,1
FITEM,2,-4
FITEM,2,9
FITEM,2,-20
FITEM,2,33
FITEM,2,-44
/GO
!*
F,P51X,AMPS,100
ALLSEL,ALL
FINISH
/SOL
/STATUS,SOLU
SOLVE
FINISH
/POST1
!*
/EFACET,1
PLNSOL, TEMP,, 0
/VIEW,1,0.343926199812 , -0.704025691051E-01,0.936353697780
/ANG, 1, 20.1435710222
/REPLO
很奇怪的是。。。。。我把电流用节点耦合方式定义之后，温度变成30度了。到底是为什么呢
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