模态叠加法，瞬态分析不能取节点位移？

xyz999

问题描述如下：

如图，一悬臂梁右端A点受正弦力激励，取B点的响应。
要求：1，使用模态叠加法；
           2，B点的位移要在计算过程中提取出来（因为后面须要根据B点的位移计算出控制力，并加载到悬臂梁上）；


代码如下：

/PREP7  

ET,1,SOLID45

MP,EX,1,210e9  
MP,PRXY,1,0.33
MP,DENS,1,7800

block,0,0.1,0,0.02,0,0.004
vmesh,1

del_time = 5e-6
total_time_step = 20

fndid1 = node(0.1,0.01,0.004)
sensor1 = node(0.1,0.01,0)

pi = acos(-1.0)
am = 8              ! amplitude
ww = 2*pi*400.0  

*dim, sensorpos1,, total_time_step, 4

! -------Modal Analysis----------------------------
/solu
antype,modal

allsel
nsel,s,loc,x,0
d,all,all,0

allsel
modopt,lanb,20
mxpand,20

outres, all, all

solve
finish

! ------------------------------------------------
! transient analysis
/solu
antype, trans
trnopt,msup,20

lumpm, 0
eqslv, spar
kbc, 1
nsubst, 1, 0, 0
deltime,del_time

outres, all, none
outres, nsol, all

allsel
solve

curr_time = 0.0

*do, nn, 1, total_time_step, 1

    ! apply force
    t1 = (nn-1)*del_time         ! time
    fff = am*sin(ww*t1)
    f, fndid1, fz, fff
   
    curr_time = curr_time + del_time

    time, curr_time
    solve
   
    ! save information
    sdx = ux(sensor1)                   ！这一行及下面两行取得的结果为什么都是0？
    sdy = uy(sensor1)
    sdz = uz(sensor1)
        
    sensorpos1(nn, 1) = curr_time
    sensorpos1(nn, 2) = sdx
    sensorpos1(nn, 3) = sdy
    sensorpos1(nn, 4) = sdz
   
*enddo
finish

!! *** expansion pass
/solu
expass,on
numexp,all
fini

!----------------------
! Write result to file
!----------------------
*cfopen, sensorpos_result, 'txt',
*vwrite, sensorpos1(1, 1), sensorpos1(1, 2), sensorpos1(1, 3), sensorpos1(1, 4)
(4E12.4)
*cfclos

计算结束后，打开文件“sensorpos_result.txt”，发现所得到的位移都是0.0，请各位高手指教，多谢！

houchenzhang

类似问题    急需求解    顶一下

gouliu100

你是在计算过程中就处理计算结果，当然没有提取出计算值，所以全为0。在实践历程后处理（POST26)中去处理结果吧