ansys分析中出现的问题！

gdayang

/PREP7
/TITLE,2D simulation

!element type
ET,1,FLUID29,,1,0               ! acoustic fluid element without ux & uy,structure absent
ET,2,plane42                    ! structural element
ET,3,fluid29                    ! acoustic fluid element with ux & uy, structure present

! material properties MP, Lab, MAT, C0, C1, C2, C3, C4
MP,DENS,1,1000
MP,SONC,1,1500
MP,EX,2,3.51e10
MP,DENS,2,2200
MP,NUXY,2,0.277

!generate a rectangle rectng,x1,x2,y1,y2
rectng,0,0.5,0,6
rectng,0.5,6,0,6

! select, assign attribute to areas and meshing them, AATT, MAT, REAL, TYPE, ESYS, SECN

!mesh area
ASEL,S,AREA,,1
AATT,1,0,1,0
ASEL,S,AREA,,2
AATT,2,0,2,0

LSEL,all
LESIZE,all,0.05, , , 1
MSHKEY,0
MSHAPE,0,2D
ASEL,all
AMESH,all

!reflect nodes and elements
nsym,x,100000,all                ! offset node number by 1000000
esym,,100000,all                 ! reflect semihole into full hole
NUMMRG,ALL  

!!!!modify element type1 of interface into element type 3
nsel,s,loc,x,0.5
esln,s,0
esel,r,type,,1
emodif,all,type,3
esel,all
nsel,all

nsel,s,loc,x,-0.5
esln,s,0
esel,r,type,,1
emodif,all,type,3
esel,all
nsel,all


! flag interface as fluid-structure interface
nsel,s,loc,x,0.5
esln,s,0
esel,r,type,,3
sf,all,fsi,1
nsel,all
esel,all

nsel,s,loc,x,-0.5
esln,s,0
esel,r,type,,3
sf,all,fsi,1
nsel,all
esel,all

nsel,all
esel,all

FINISH   

各位，用上面的命令建模，然后在井眼中的流体中某点加一个按正弦规律变化的压力源。
根据结果计算的流体速度与原来设置的流体速度差别比较大。不知道是什么原因？C:%5CDocuments%20and%20Settings%5CAdministrator%5C%E6%A1%8C%E9%9D%A2%5C%E6%9C%AA%E5%91%BD%E5%90%8D.bmp