做模态分析，外界激励47.33Hz，算出1阶，2阶频率为21Hz和45Hz,想优化设计，参数化建模已建好，怎么优化啊

/PREP7
*CREAT,OPTIM
/PREP7
*SET,T,20
K,1,-175,0,0,
K,2,-190,15,0,
K,3,-215,15,0,
K,4,-215,347,0,
K,5,-250,347,0,
k,6,-250,332,0
k,7,-270,312,0
k,8,-430,312,0
k,9,-450,332,0
k,10,-450,500,0
k,11,-430,518,0
k,12,370,518,0
k,13,390,498,0
k,14,390,357,0
k,15,370,337,0
k,16,260,337,0
k,17,250,347,0
k,18,215,347,0
k,19,215,15,0
k,20,190,15,0
k,21,175,0,0
lstr,1,2
lstr,2,3
lstr,3,4
lstr,4,5
lstr,5,6
lstr,6,7
lstr,7,8
lstr,8,9
lstr,9,10
lstr,10,11
lstr,11,12
lstr,12,13
lstr,13,14
lstr,14,15
lstr,15,16
lstr,16,17
lstr,17,18
lstr,18,19
lstr,19,20
lstr,20,21
lstr,21,1
al,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21
FLST,2,21,4
FITEM,2,21
FITEM,2,1
FITEM,2,2
FITEM,2,3
FITEM,2,4
FITEM,2,5
FITEM,2,6
FITEM,2,7
FITEM,2,8
FITEM,2,9
FITEM,2,10
FITEM,2,11
FITEM,2,12
FITEM,2,13
FITEM,2,14
FITEM,2,15
FITEM,2,16
FITEM,2,17
FITEM,2,18
FITEM,2,19
FITEM,2,20
AL,P51X
LPLOT
k,31,-175,40,0
k,32,-175,347,0
k,33,175,347,0
k,34,175,40,0
lstr,31,32
lstr,32,33
lstr,33,34
lstr,34,31
k,31,-175,40,0
k,32,-175,347,0
k,33,175,347,0
k,34,175,40,0
lstr,31,32
lstr,32,33
lstr,33,34
lstr,34,31
FLST,2,4,4
FITEM,2,25
FITEM,2,24
FITEM,2,23
FITEM,2,22
AL,P51X
APLOT
ASBA, 1, 2
CYL4,-350,410,66
ASBA, 3, 1
*SET,T,20
!*
VOFFST,2,T, ,
!*
ET,1,92
!*
!*
MPTEMP,,,,,,,,
MPTEMP,1,0
MPDATA,EX,1,,2.06E8
MPDATA,PRXY,1,,0.3
MPTEMP,,,,,,,,
MPTEMP,1,0
MPDATA,DENS,1,,7.85E-6
SMRT,6
SMRT,2
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
!*
!*
ANTYPE,2
!*
!*
MODOPT,LANB,5
EQSLV,SPAR
MXPAND,5, , ,0
LUMPM,0
PSTRES,0
!*
MODOPT,LANB,5,0,0, ,OFF
FLST,2,2,5,ORDE,2
FITEM,2,3
FITEM,2,23
!*
/GO
DA,P51X,ALL,
/STATUS,SOLU
SOLVE
/POST1
SET,LAST
ETABLE,EVOL,VOLU
SSUM
*GET,VTOT,SSUM,,ITEM,EVOL

*GET,ifreq,MODE,1,FREQ

/opt
OPANL,tong,lgw

!*
OPVAR,T,DV,10,25,0.1,
!*
OPVAR,IFREQ,SV,75, , ,
!*
OPVAR,VTOT,OBJ, , , ,
!*
OPTYPE,SUBP
OPSUBP,30,7,
OPEQN,0,0,0,0,0,
!*
OPDATA,'tong','opt',' '
OPLOOP,TOP,IGNO,SCAL
OPPRNT,OFF
OPKEEP,OFF
!*
OPEXE
OPLIST,ALL
!*
XVAROPT,' '
PLVAROPT,VTOT
!*
/POST1
SET,LAST
ETABLE,EVOL,VOLU
SSUM
*GET,VTOT,SSUM,,ITEM,EVOL
RHO=7.8E-6
WT=RHO*VTOT
*GET,FREQ1,MODE,1,FREQ !*将第一阶频率给REQ1
/OPT !*优化控制
OPANL,OPTIM

!*
OPVAR,T,DV,10,25,0.1, !*定义T取值范围
!*
OPVAR,FREQ1,SV,75, , , !*使FREQ1大于75
!*
OPVAR,WT,OBJ, , , ,
!*
OPTYPE,SUBP
OPSAVE,OPTCIRCLE,OPT0 !*定义优化方法
OPLIST,ALL,,1
OPEXEC !*