[声学分析] 声学噪声模拟问题（大家帮忙看看。版主一定要看啊）
声学噪声模拟问题（大家帮忙看看。版主一定要看啊）我想做一个发动机加隔声罩后看隔声罩一米远处的噪声情况。噪声源（发动机）采用直径为0.3米的实心圆代替，采用solid45单元，其属性设置为：mp,ex,1,2.10e11
mp,dens,1,7600
mp,nuxy,1,0
mp,sonc,1,4800
在实心圆外加一个厚度为0.03米空心圆（空气），在两圆的接触面上施加声固耦合和声压载荷：
选取接触面上的所有点，我用的是下面的命令施加的：
SF,ALL,FSI 声固耦合
D,ALL,PRES,2.12 声压载荷（声压级在100dB左右）
0.03米的空心圆属性设置为：
et,2,fluid30
mp,dens,2,1.21
mp,sonc,2,344
R,2,20e-6
mp,mu,2,0.02
外面就是一个内空的长方体作为吸声结构，其属性设置为：
et,3,fluid30,,1,0
mp,ex,3,1e9
mp,nuxy,3,0.2
mp,dens,3,30
mp,sonc,3,800
mp,mu,3,0.9
R,3,20e-6
在最外面用一个球体来模拟无限远处的吸声面，球体内部设置为空气，et,3,fluid30,,1,0
在球体最外表面，选取表面上的所有点，设置属性为：
et,4,fluid130
mp,dens,2,1.21
mp,sonc,2,344
mp,mu,2,0.02
R,4,4（球体直径为4米）
运用ESURF命令生成无限远处吸声表面。
我大体上是这么做的，可是结果太离谱了，我查看点的计算结果数值有几百的，我输入的才是2.12啊，不知道问题出在哪，请各位大侠帮忙看看，有什么我做的不对的。
还有就是我看声压值有实部虚部之分，这个都怎么进行查看啊？最终要的结构怎么生成啊？我很疑惑，我是个初学者，请大家多多关照
/PREP7
SPH4,0,0,4 模型结构建立
BLOCK,1.7,-1.7,1.4,-1.4,1.4,-1.4,
/VIEW,1,1,2,3
/ANG,1
/REP,FAST
LPLOT
FLST,2,2,6,ORDE,2
FITEM,2,1
FITEM,2,-2
VOVLAP,P51X
LPLOT
BLOCK,0.7,-0.7,0.4,-0.4,0.4,-0.4,
FLST,2,2,6,ORDE,2
FITEM,2,1
FITEM,2,-2
VOVLAP,P51X
LPLOT
BLOCK,0.65,-0.65,0.35,-0.35,0.35,-0.35,
FLST,2,2,6,ORDE,2
FITEM,2,1
FITEM,2,-2
VOVLAP,P51X
LPLOT
BLOCK,-0.6,-0.47,0.08,0.14,0.35,0.38,
FLST,2,2,6,ORDE,2
FITEM,2,1
FITEM,2,5
VOVLAP,P51X
LPLOT
BLOCK,0.6,0.47,0.08,0.14,0.35,0.38,
FLST,2,2,6,ORDE,2
FITEM,2,5
FITEM,2,-6
VOVLAP,P51X
LPLOT
BLOCK,0.6,0.47,0.08,-0.125,0.365,0.38,
BLOCK,-0.6,-0.47,0.08,-0.125,0.365,0.38,
FLST,2,3,6,ORDE,2
FITEM,2,6
FITEM,2,-8
VOVLAP,P51X
LPLOT
FLST,2,2,6,ORDE,2
FITEM,2,1
FITEM,2,9
VADD,P51X
FLST,2,2,6,ORDE,2
FITEM,2,5
FITEM,2,-6
VADD,P51X
LPLOT
BLOCK,-0.6,-0.47,-0.11,-0.125,0.4,0.38,
BLOCK,-0.6,-0.47,-0.085,-0.1,0.4,0.38,
BLOCK,-0.6,-0.47,-0.075,-0.06,0.4,0.38,
BLOCK,-0.6,-0.47,-0.035,-0.05,0.4,0.38,
BLOCK,-0.6,-0.47,-0.025,-0.01,0.4,0.38,
BLOCK,0.6,0.47,-0.025,-0.01,0.4,0.38,
BLOCK,0.6,0.47,-0.035,-0.05,0.4,0.38,
BLOCK,0.6,0.47,-0.06,-0.075,0.4,0.38,
BLOCK,0.6,0.47,-0.1,-0.085,0.4,0.38,
BLOCK,0.6,0.47,-0.11,-0.125,0.4,0.38,
FLST,2,11,6,ORDE,4
FITEM,2,5
FITEM,2,-6
FITEM,2,8
FITEM,2,-16
VOVLAP,P51X
FLST,2,6,6,ORDE,3
FITEM,2,5
FITEM,2,-9
FITEM,2,11
VADD,P51X
FLST,2,6,6,ORDE,4
FITEM,2,1
FITEM,2,12
FITEM,2,-15
FITEM,2,17
VADD,P51X
FLST,2,3,6,ORDE,3
FITEM,2,2
FITEM,2,5
FITEM,2,10
VADD,P51X
VSEL,S, , , 1
VPLOT
LPLOT
alls
SPH4,0,0,0.32
FLST,2,2,6,ORDE,2
FITEM,2,1
FITEM,2,-2
VOVLAP,P51X
LPLOT
SPH4,0,0,0.3
FLST,2,2,6,ORDE,2
FITEM,2,1
FITEM,2,-2
VOVLAP,P51X
LPLOT
NUMMRG,ALL, , , ,LOW
BLOCK,0.7,0.67,0.1,0.3,0.2,-0.2,
FLST,2,2,6,ORDE,2
FITEM,2,2
FITEM,2,4
VADD,P51X
LPLOT
NUMMRG,ALL, , , ,LOW
BLOCK,0.62,0.65,0.07,0.33,0.23,-0.23,
FLST,2,2,6,ORDE,2
FITEM,2,2
FITEM,2,5
VOVLAP,P51X
LPLOT
FLST,2,2,6,ORDE,2
FITEM,2,2
FITEM,2,7
VADD,P51X
LPLOT
SAVE
NUMMRG,ALL, , , ,LOW
et,1,solid45 ：单元定义
et,2,fluid30
et,3,fluid30,,1,0
et,4,fluid130
mp,ex,1,2.10e11 ：噪声源属性（钢结构）
mp,dens,1,7600
mp,nuxy,1,0
mp,sonc,1,4800
CM,_Y,VOLU
VSEL, , , , 1
CM,_Y1,VOLU
CMSEL,S,_Y
!*
CMSEL,S,_Y1
VATT, 1, , 1, 0
CMSEL,S,_Y
CMDELE,_Y
CMDELE,_Y1
!*
mp,dens,2,1.21 ：空气属性
mp,sonc,2,344
R,2,20e-6
mp,mu,2,0.02
：吸声材料属性
mp,dens,3,30
mp,sonc,3,800
mp,mu,3,0.9
R,3,20e-6
CM,_Y,VOLU
VSEL, , , , 6
CM,_Y1,VOLU
CMSEL,S,_Y
!*
CMSEL,S,_Y1
VATT, 2, 2, 2, 0
CMSEL,S,_Y
CMDELE,_Y
CMDELE,_Y1
!*
CM,_Y,VOLU
VSEL, , , , 4
CM,_Y1,VOLU
CMSEL,S,_Y
!*
CMSEL,S,_Y1
VATT, 2, 2, 3, 0
CMSEL,S,_Y
CMDELE,_Y
CMDELE,_Y1
!*
CM,_Y,VOLU
VSEL, , , , 5
CM,_Y1,VOLU
CMSEL,S,_Y
!*
CMSEL,S,_Y1
VATT, 3, 3, 3, 0
CMSEL,S,_Y
CMDELE,_Y
CMDELE,_Y1
!*
CM,_Y,VOLU
VSEL, , , , 8
CM,_Y1,VOLU
CMSEL,S,_Y
!*
CMSEL,S,_Y1
VATT, 2, 2, 3, 0
CMSEL,S,_Y
CMDELE,_Y
CMDELE,_Y1
!*
CM,_Y,VOLU
VSEL, , , , 3
CM,_Y1,VOLU
CMSEL,S,_Y
!*
CMSEL,S,_Y1
VATT, 2, 2, 3, 0
CMSEL,S,_Y
CMDELE,_Y
CMDELE,_Y1
!*
esize,0.05
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
!*
LPLOT
CM,_Y,VOLU
VSEL, , , , 6
CM,_Y1,VOLU
CHKMSH,'VOLU'
CMSEL,S,_Y
!*
VMESH,_Y1
!*
CMDELE,_Y
CMDELE,_Y1
CMDELE,_Y2
!*
LPLOT
NUMMRG,ALL, , , ,LOW
CM,_Y,VOLU
VSEL, , , , 4
CM,_Y1,VOLU
CHKMSH,'VOLU'
CMSEL,S,_Y
!*
VMESH,_Y1
!*
CMDELE,_Y
CMDELE,_Y1
CMDELE,_Y2
!*
LPLOT
NUMMRG,ALL, , , ,LOW
CM,_Y,VOLU
VSEL, , , , 5
CM,_Y1,VOLU
CHKMSH,'VOLU'
CMSEL,S,_Y
!*
VMESH,_Y1
!*
CMDELE,_Y
CMDELE,_Y1
CMDELE,_Y2
!*
LPLOT
esize,0.15
CM,_Y,VOLU
VSEL, , , , 8
CM,_Y1,VOLU
CHKMSH,'VOLU'
CMSEL,S,_Y
!*
VMESH,_Y1
!*
CMDELE,_Y
CMDELE,_Y1
CMDELE,_Y2
!*
LPLOT
NUMMRG,ALL, , , ,LOW
esize,0.3
CM,_Y,VOLU
VSEL, , , , 3
CM,_Y1,VOLU
CHKMSH,'VOLU'
CMSEL,S,_Y
!*
VMESH,_Y1
!*
CMDELE,_Y
CMDELE,_Y1
CMDELE,_Y2
!*
LPLOT
FLST,5,2,5,ORDE,2
FITEM,5,23
FITEM,5,25
ASEL,S, , ,P51X
APLOT
NSLA,S,1
NPLOT
FINISH
/SOL
!*
ANTYPE,3
FLST,5,516,1,ORDE,2
FITEM,5,1
FITEM,5,-516
CM,_Y,NODE
NSEL,R, , ,P51X
CM,_Y1,NODE
CMSEL,S,_Y
CMDELE,_Y
!*
/GO
!*
D,_Y1,PRES,2.12 在钢球（噪声源表面施加2.12pa的声压）
!*
CMDELE,_Y1
!*
FLST,2,516,1,ORDE,2
FITEM,2,1
FITEM,2,-516
SF,P51X,FSI 在钢球（噪声源）与空气接触表面施加声固耦合（只在这里施加了声固耦合）
alls
LPLOT
FLST,5,2,5,ORDE,2
FITEM,5,1
FITEM,5,-2
ASEL,S, , ,P51X
NSLA,S,1
NPLOT
/DIST,1,1.08222638492,1
/REP,FAST
/DIST,1,1.08222638492,1
/REP,FAST
/DIST,1,1.08222638492,1
/REP,FAST
FINISH
/PREP7
R,4,4,,,,
!*
TYPE, 4
MAT, 2
REAL, 4
ESYS, 0
SECNUM,
!*
esurf
LPLOT
alls
SAVE
FINISH
/SOL
HARFRQ,2000,2000,
NSUBST, ,
KBC,0
!*
/STATUS,SOLU
SOLVE 问题挺简单，做的太复杂，这个问题用sysnoise好解决一点；
以前我也用ansys分析声学问题，发现设定麻烦，比如偶合，无限元等使用相当的不方便，更关键的是计算结果可信度不大，毕竟声学模块是ansys的弱项。 原帖由 hhhjjjhwc 于 2009-2-28 13:08 发表 http://www.chinavib.com/forum/images/common/back.gif
问题挺简单，做的太复杂，这个问题用sysnoise好解决一点；
以前我也用ansys分析声学问题，发现设定麻烦，比如偶合，无限元等使用相当的不方便，更关键的是计算结果可信度不大，毕竟声学模块是ansys的弱项。
sysnoise的高频分析是不是差很多阿，比如分析到5000hz，网格又要密集，但是本身内存才500m，矛盾了。。。。 不要用有限元啊，用边界元啊！！ 回复 2 # hhhjjjhwc 的帖子
主任您好；
我想用ANSYS算下噪声（没有sysnoise软件），噪声源（电机）采用plane42属性设置密度，速度，摩擦系数还是设置成弹性模量，泊松比，密度。望指点下。谢谢。 回复 4 # hhhjjjhwc 的帖子
还有用ANSYSY计算噪声的时候，用什么场呢？刚接触这，资料好少··
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