结构拓扑优化

哪位高手做过拓扑优化啊，求指导，我用ansys13做结构拓扑优化，命令流如下：
/TITLE,M
/PREP7
BLC4,0,0,3,1
ET,1,82
ET,2,82
MP,EX,1,118E9
MP,NUXY,1,0.3
ESIZE,0.05
TYPE,1
AMESH,ALL
NSEL,S,LOC,X,0,0.4
ESLN
TYPE,2
EMODI,ALL
ALLSEL
NSEL,S,LOC,X,0
D,ALL,ALL,0
NSEL,S,LOC,X,3
D,ALL,ALL,0
*SET,FORCE,1000
NSEL,S,LOC,X,1
NSEL,R,LOC,Y,1
F,ALL,FY,FORCE
ALLSEL
LSWRITE,1
FDEL,ALL
NSEL,S,LOC,X,2
NSEL,R,LOC,Y,0
F,ALL,FY,-FORCE
ALLSEL
LSWRITE,2
FDEL,ALL
TODEF,50,2
TOCOMP,MCOMP,MULTIPLE,2
TOVAR,MCOMP,OBJ
TOVAR,VOLUME,CON,,50
TOTYPE,OC
TODEF
/DSCALE,,OFF
/CONTOUR,,2
TOLOOP,12,1
SAVE
SAVE
/FILNAME,toopt,0
做的时候弹出错误提醒a type 1 topology optimization element has been detected referring to an element type which is not supported for topological optimization.The todef command is ignored.请路过的大侠帮忙看下啊