【问题描述】在加载时，由于一些特殊需求，如何将面压力荷载转化为等效节点荷载施加
【解决方案】没有直接转化的办法。但是有个间接转化的办法，即对目标面施加面压力P，然后约束所有的节点的所有自由度，求解，得到各节点的荷载就是想要的等效节点荷载~



~~~~~~~~~~~~以下为ansys的apdl命令流~~~~~~
!!!对正方体上表面施加200pa的面压力~
finish
/clear
/title,ANSYS实例教程公众号 !中文容易出现乱码
/prep7
et,1,solid185
mp,ex,1,2e10
mp,prxy,1,0.3
mp,dens,1,1000
block,1,0,1,0,1,0
esize,0.5
vatt,1,,1
vmesh,all
allsel
asel,s,loc,z,1
sfa,all,,pres,200
allsel
d,all,all,0
allsel
/solu
solve
fini
/post1
prnld,f
!!!以下为求解的等效的节点荷载~
print f summed nodal loads
***** post1 summed total nodal loads listing *****
load step= 1 substep= 1
time= 1.0000 load case= 0
the following x,y,z solutions are in the global coordinate system
node fx fy fz
10 -12.500
11 -12.500
12 -25.000
13 -12.500
14 -25.000
15 -12.500
16 -25.000
17 -25.000
18 -50.000
total values
value 0.0000 0.0000 -200.00
!!!【接下来验证一下分别施加面荷载、节点荷载后的结果已否一致】
!!【验证1：加载面压力】
finish
/clear
/title,ANSYS实例教程公众号 !中文容易出现乱码
/prep7
et,1,solid185
mp,ex,1,2e10
mp,prxy,1,0.3
mp,dens,1,1000
block,1,0,1,0,1,0
esize,0.5
vatt,1,,1
vmesh,all
allsel
asel,s,loc,z,1
sfa,all,,pres,200
allsel
nsel,s,loc,z,0
d,all,all,0
allsel
/solu
solve
fini
/post1
presol,f
!!【验证2加载节点压力】
finish
/clear
/title,ANSYS实例教程公众号 !中文容易出现乱码
/prep7
et,1,solid185
mp,ex,1,2e10
mp,prxy,1,0.3
mp,dens,1,1000
block,1,0,1,0,1,0
esize,0.5
vatt,1,,1
vmesh,all
f,10,fz,-12.5
f,11,fz,-12.5
f,12,fz,-25
f,13,fz,-12.5
f,14,fz,-25
f,15,fz,-12.5
f,16,fz,-25
f,17,fz,-25
f,18,fz,-50
allsel
nsel,s,loc,z,0
d,all,all,0
allsel
/solu
solve
fini
/post1
presol,f
两者对应的结果如下~结果完全一致~~