薄膜太薄时收敛问题

玉林

薄壳收敛问题，当壳的厚度比较大时可以收敛，小的时候就不收敛了。膜厚度R,1,0.03, , , , , ,时收敛，但是R,1,0.03/10, , , , , ,不收敛，我给它加了阻尼，但是不起作用。
下面是我的命令流
FINISH  ! Make sure we are at BEGIN level   
/CLEAR,NOSTART  ! Clear model since no SAVE found   
/PREP7  
BOPTN,KEEP,0
BOPTN,NWARN,0   
BOPTN,VERS,RV52
BTOL,1e-005,
/PNUM,KP,0  
/PNUM,LINE,0
/PNUM,AREA,1
/PNUM,VOLU,0
/PNUM,NODE,0
/PNUM,TABN,0
/PNUM,SVAL,0
/NUMBER,0   
!*  
/PNUM,MAT,0
!*  
!*  
ET,1,SHELL181  
KEYOPT,1,1,0
KEYOPT,1,3,2
!
ET,2,BEAM44  
!*   
!*
!* 膜材料
!*   
MPTEMP,,,,,,,,  
MPTEMP,1,0  
MPDATA,EX,1,,15e9   
MPDATA,PRXY,1,,0.3  
MPDATA,DENS,1,,0.1/0.0003
MPDATA,BETA,1,,0.05

!
!*
!*  膜厚度
!*  
R,1,0.03/10, , , , , ,
RMORE, , , ,
RMORE   
RMORE, ,

/PREP7  


RECTNG,-10,10,-10,10,   

TYPE,   1   
MAT,       1
REAL,       1   
ESYS,       0   
SECNUM,
!*  
!*定义网格密度
!*  
LESIZE,ALL,0.5, , , ,1, , ,1,   


MSHAPE,1,2D
MSHKEY,0
AMESH, 1

ALLSEL,ALL

/GO
SFA,1,1,PRES,400
DK,1, , , ,0,ALL, , , , , ,
DK,2, , , ,0,ALL, , , , , ,
DK,3, , , ,0,ALL, , , , , ,
DK,4, , , ,0,ALL, , , , , ,

finish

   /solu
   antype,static
   nropt,full, ,on
   nlgeom,on
   pstr,on        ! prestress analysis
   sstif,on
   NSUBST,20,  
   AUTOTS,on  
   TIME,1  
   LUMPM,0  
   EQSLV, , ,0,  
   PRECISION,0  
   MSAVE,0  
   PIVCHECK,1   
   ematwrite,yes   
   OUTRES,ERASE
   OUTRES,ALL,ALL  

   solve
   fini
出现的错误为

计算到最后不收敛，如下图