节点等效应力为什么无法排列？

cyh3278

!塔体循环泵管架
cgxh=12.6
!材料参数
YOUNG=210E9
DENSITY=7850
/PREP7
!定义槽钢型号
*IF,cgxh,EQ,8,THEN
        cgh=80E-3
        cgb=43E-3
        cgd=5E-3
*ELSEIF,cgxh,EQ,10
        cgh=100E-3
        cgb=48E-3
        cgd=5.3E-3
*ELSEIF,cgxh,EQ,12.6
        cgh=126E-3
        cgb=53E-3
        cgd=5.5E-3
*ELSEIF,cgxh,EQ,14
        cgh=140E-3
        cgb=60E-3
        cgd=8E-3
*ELSEIF,cgxh,EQ,16
        cgh=160E-3
        cgb=65E-3
        cgd=8.5E-3
*ELSEIF,cgxh,EQ,18
        cgh=180E-3
        cgb=70E-3
        cgd=9E-3
*ELSEIF,cgxh,EQ,20
        cgh=200E-3
        cgb=75E-3
        cgd=9E-3
*ENDIF
MP,EX,1,YOUNG
MP,NUXY,1,0.3
MP,DENS,1,DENSITY
ET,1,BEAM188
SECTYPE,   1, BEAM, CHAN, , 0   
SECOFFSET, USER, 0, 0
SECDATA,cgb,cgb,cgh,cgd,cgd,cgd,0,0,0,0
!SECDATA,hxncxgw1,hxncxgw1,hxncxgw2,hxncxgt1,hxncxgt1,hxncxgt2,0,0,0,0
K,1,0,0,0
K,2,2,0,0
K,3,0,10,0
L,1,2
lsel,all
LESIZE,ALL,,,20   
LATT,1,1,1,,3,,1  !!!!!!!!!!!!!!!!!!!!!!!!!!!
LMESH,ALL
!以单元显示
/REPLOT
EPLOT
/ESHAPE,1
KSEL,S,KP,,1,1
DK,ALL,ALL
KSEL,S,KP,,2,2
FK,ALL,FY,-1380
allsel
/solu
solve
/POST1  
NSORT,S,EQV            !将节点等效应力排序

当运行到NSORT,S,EQV时，系统显示No NSORT is avaiable for the selected set。这是说明原因？

16443

仔细参看beam188的单元输出说明