几个ansys流固耦合的例子

1、一般说来，ANSYS的流固耦合主要有4种方式：1，sequential这需要用户进行APDL编程进行流固耦合sequentia指的是顺序耦合以采用MpCCI为例，你可以利用ANSYS和一个第三方CFD产品执行流固耦合分析。在这个方法中，基于网格的平行代码耦合界面(MpCCI)将ANSYS和CFD程序耦合起来。即使网格上存在差别，MpCCI也能够实现流固界面的数据转换。ANSYSCD中包含有MpCCI库和一个相关实例。关于该方法的详细信息，参见ANSYSCoupled-FieldAnalysisGuide中的SequentialCouplin2，FSIsolver流固耦合的设置过程非常简单，推荐

2、你使用这种方式3，multi-fieldsolver这是FSIsolver的扩展，你可以使用它实现流体，结构，热，电磁等的耦合4，直接采用特殊的单元进行直接耦合，耦合计算直接发生在单元刚度矩阵一个流固耦合的例子length=2width=3height=2/prep7et，1，63et,2,30!选用FLUID30单元，用于流固耦合问题r，1，0.01mp,ex,1,2e11mp,nuxy,1,0.3mp,dens,1,7800mp,dens,2,1000!定义Acoustics材料来描述流体材料-水mp,sonc,2,1400mp,mu,0,!block,length,width,heigh

3、tesize,0.5mshkey,1!type,1mat,1real,1asel,u,loc,y,widthamesh,allalls!type,2mat,2vmesh,allfini/soluantype,2modopt,unsym,10!非对称模态提取方法处理流固耦合问题eqslv,frontmxpand,10,1nsel,s,loc,x,nsel,a,loc,x,lengthnsel,r,loc,yd,all,ux,uy,uz,nsel,s,loc,y,width,d,all,pres,0allsasel,u,loc,y,width,sfa,all,fsi!定义流固耦合界面allssol

4、vfini/post1set,firstplnsol,u,sum,2,1fini再给大家一个实例！考虑结构在水中的自振频率：例子是一加筋板在水中的模态分析命令流如下：FINISH/CLEAR/FILENAME,plane/UNITS,SI/TITLE,plane/PREP7!*ELEMENTDEFINE*ET,63,63ET,4,beam4et,30,fluid30!*MATERIALDEFINE*MP,EX,1,2.10E11MP,DENS,1,7850MP,NUXY,1,0.3mp,dens,30,1025mp,sonc,30,1500mp,mu,30,0.5!*REALCONSTANT*

5、r,30,1e-06r,50,0.05r,75,0.375e-02,0.78125e-06,0.000016406k,1k,4,1kfill,1,4,2,1kgen,4,1,4,1,1/3,10a,1,2,12,11*do,i,0,2*do,j,0,2*10,10a,1+i+j,2+i+j,12+i+j,11+i+j*enddo*enddok,100,-14.5,-14.5k,101,-14.5,15.5k,102,15.5,15.5k,103,15.5,-14.5k,140,-14.5,-14.5,30k,141,-14.5,15.5,30k,142,15.5,15.5,30k,143,15

6、.5,-14.5,30a,100,101,102,103,4,14,24,34,33,32,31,21,11,1a,1,2,3,4,103,100a,140,141,142,143a,100,101,141,140a,101,102,142,141a,142,143,103,102a,140,143,103,100a,14,24,34,33,32,31,21,11,1,2,3,4asel,u,1,FLST,2,8,5,ORDE,2FITEM,2,10FITEM,2,-17VA,P51Xnummrg,allallsMSHKEY,0M

7、SHAPE,0esize,1lsel,s,loc,y,1/3lsel,r,loc,x,0,1lsel,r,loc,z,0latt,1,75,4lmesh,alllsel,s,loc,y,2/3lsel,r,loc,x,0,1lsel,r,loc,z,0latt,1,75,4lmesh,alllsel,s,loc,x,1/3lsel,r,loc,y,0,1lsel,r,loc,z,0latt,1,75,4lmesh,alllsel,s,loc,x,2/3lsel,r,loc,y,0,1lsel,r,loc,z,0latt,1,75,4lmesh,allasel,s,1,9aatt,1,50,63

8、amesh,allallsMSHAPE,1,3desize,3vsel,s,1type,30$mat,30$real,30vmesh,allallsFINISH/solualls!*求解*tTTxTxTxTxTxTxTxTxTxTxTxTxTxTxTxTxTxTxTxTxTxANTYPE,MODALMODOPT,lanb,25,0SOLVEFINISH总是出现error说矩阵不对称，不可以用lanb计算。总结：流体单元不能用对称的解法应该采用非对称解法。例子是一圆环在水中的模态分析。命令流如下：finish/clear/PREP7!定义单元类型ET,1,PLANE42!structuralel

9、ementET,2,FLUID29!acousticfluidelementwithux&uyET,3,129!acousticinfinitelineelementr,3,0.31242,0,0ET,4,FLUID29,1,0!acousticfluidelementwithoutux&uy!材料属性MP,EX,1,2.068e11MP,DENS,1,7929MP,NUXY,1,0MP,DENS,2,1030MP,SONC,2,1460!创建四分之一模型CYL4,0,0,0.254,0,0.26035,90CYL4,0,0,0.26035,0,0.31242,90!选择属性,网格划分ASEL

10、,S,AREA,1AATT,1,1,1,0LESIZE,1,16,1LESIZE,3,16,1LESIZE,2,1,1LESIZE,4,1,1MSHKEY,1MSHAPE,0,2D!mappedquadmeshAMESH,1ASEL,S,AREA,2AATT,2,1,2,0LESIZE,5,16,1LESIZE,7,16,1LESIZE,6,5LESIZE,8,5MSHKEY,0MSHAPE,0,2D!mappedquadmeshAMESH,2!关于Y轴镜像nsym,x,1000,all!offsetnodenumberby1000esym,1000,all!关于y轴镜像nsym,y,2000

11、,all!offsetnodenumberby2000esym,2000,allNUMMRG,ALL!mergeallquantitiesesel,s,type,1nsle,sesln,s,0nsle,sesel,invensle,semodif,all,type,4esel,allnsel,all!指定无限吸收边界csys,1nsel,s,loc,x,0.31242type,3real,3mat,2esurfesel,allnsel,all!标识流固交接面nsel,s,loc,x,0.26035esel,s,type,2sf,all,fsi,1nsel,allesel,allFINISH/s

12、oluantype,modalmodopt,damp,10mxpand,10,yessolvefinish为了便于对比，也对圆环在空气中做了模态分析finish/clear/PREP7!定义单元类型ET,1,PLANE42!structuralelement!材料属性MP,EX,1,2.068e11MP,DENS,1,7929MP,NUXY,1,0!创建四分之一模型CYL4,0,0,0.254,0,0.26035,90!选择属性,网格划分ASEL,S,AREA,1AATT,1,1,1,0LESIZE,1,16,1LESIZE,3,16,1LESIZE,2,1,1LESIZE,4,1,1MSHK

13、EY,1MSHAPE,0,2D!mappedquadmeshAMESH,1!关于Y轴镜像nsym,x,1000,all!offsetnodenumberby1000esym,1000,all!关于y轴镜像nsym,y,2000,all!offsetnodenumberby2000esym,2000,allNUMMRG,ALL/soluantype,modalmodopt,lanb,10mxpand,10,yessolvefinish在水中的自振频率为SETTIME/FREQLOADSTEPSUBSTEPCUMULATIVE1-0.19544E-101110.29640E-031113-0.21

14、663E-101224-0.29640E-0312250.30870E-0313360.00001337-0.30870E-0314480.00001449-0.53726E-03155100.57522E-11155110.53726E-0316612-0.89057E-111660.98059E-0117735.2321770.98059E-01188-35.2321880.98061E-0119935.2331990.98061E-0111010-35.23311010在空气中的自振频率为SETTIME/FREQLOADSTEPSUBSTEPCUMULATIVE10.000011120.

15、00001220.73609E-0313360.80514460.805155172.97166172.97177334.40188334.40199546.5911010主要有以下疑问：1）考虑流固耦合，做模态分析时流体单元是否只能用fluid29（2d）和fluid30（3d），对于fluidl29和fluid130在耦合中具体起到什么作用，能不能不设，而用边界约束条件代替？2）流体范围怎样确定，如本例中（CYL4,0,0,0.26035,0,0.31242,90）,外半径为0.31242。如果不是环形的，如一块当水板，该怎样考虑？3）如果不考虑流体的压缩性，把声速设的很大，MP,SONC

16、,2,1e20，就可以了。4）从自振频率可以看出，在水中和在空气中，圆环的自振频率差别特别大，且振型也大相径庭，为什么？在水中时，模态提取方法用damp（为什么不能用unsym）,特征值的虚部代表角频率，为什么第一阶为正，第二阶为负，而第三阶和第四阶都为0，第六阶、八阶、十阶都为负。应该是从小到大才对？5）在空气中时，模态提取方法用lanb，为什么第一阶第二阶的频率都为0。请高手指点迷津，急盼中对以上问题的解答：频率为零，一般是发生了刚体位移，估计你是把水抽走，而没有限制圆环。1。圆环在水中振动必然导致波动（其实就是声波）在水中传播，当声波到达水的另一个界面时就会发生反射（除非水和另一个相邻体

17、的声阻抗是匹配的）。水和金属中的声速相差不大，即可压缩性相差不大。两种可压缩性相差不大的物质的相互作用对两者影响都很大。圆环在水中振动，水对圆环的反作用是由于反射波引起的，流固耦合中采用fluid129和130就是最大程度的减弱反射波。2。声波从圆环开始传播，随着传播距离的增加，波阵面不断增大，振幅不断减小。同时由于水的衰减，声波也不断减弱。如果水的空间越大，则反射波返回圆环的路径越长，衰减也就越多，影响也就越小。fluid129和130对反射波的衰减（通过很小的反射实现）有限，因此还需要水要有足够的空间。fluidl29和130离结构应该大于0.2U2c/f,c为水中声速）。以上的做法在误差

18、允许的情况下等效于水在无限大水空间中的情况。如果是挡水板，水就是有限空间了，情况也不一样。3。声速加大情况也不一样，就是不知是不是你所要的情况？4。空气作为介质，由于其声速比金属小很多，可压缩性大很多，影响可以忽略不计。而水的影响就不同了。这可能就是频率和振型不同的原因吧？我试了你的例子，各种提取方法都可以。5。空气的影响忽略不计，因此需要对圆环进行约束。你没有约束，那么就会发生静态位移即频率为零。圆环有两个对称轴，因此会发生频率成对出现的情况。也就是说，两个方向上有同样的振型。接触分析实例-包含初始间隙fini/clear,nostart/prep7et,1,82KEYOPT,1,3,3r,

19、1,0.5mp,ex,1,1e9mp,prxy,1,0.3k,1,0,0k,2,10,0k,3,10,5k,4,6.2,5k,5,7.5,3.4k,6,2.5,3.4k,7,3.8,5k,8,0,5a,1,2,3,4,5,6,7,8LFILLT,6,5,0.18,LFILLT,5,4,0.18,FLST,2,3,4FITEM,2,9FITEM,2,11FITEM,2,10AL,P51XFLST,2,3,4FITEM,2,13FITEM,2,14FITEM,2,12AL,P51XFLST,2,3,5,ORDE,2FITEM,2,1FITEM,2,-3AADD,P51Xrect,0,10,4.8,

20、5ASBA,4,1gap=0.02k,24,6.2-gap,5k,25,7.5-gap,3.4k,26,2.5+gap,3.4k,27,3.8+gap,5a,24,25,26,27LFILLT,4,3,0.2,LFILLT,3,2,0.2,FLST,2,3,4FITEM,2,7FITEM,2,10FITEM,2,8AL,P51XFLST,2,3,4FITEM,2,13FITEM,2,14FITEM,2,11AL,P51XFLST,3,2,5,ORDE,2FITEM,3,3FITEM,3,-4ASBA,1,P51Xrect,3.8+gap,6.2-gap,5,10rect,3.8+gap,3.8

21、+gap+8,10,12FLST,2,3,5,ORDE,3FITEM,2,1FITEM,2,3FITEM,2,5AADD,P51Xrect,3.8+gap+8,3.8+gap+8+2,10,12FLST,2,2,5,ORDE,2FITEM,2,1FITEM,2,4AGLUE,P51XCYL4,2.0,1.8,0.6CYL4,7.0,1.8,0.6FLST,2,3,5,ORDE,3FITEM,2,2FITEM,2,4FITEM,2,-5AOVLAP,P51Xesize,0.2amesh,allFLST,5,135,2,ORDE,32FITEM,5,485FITEM,5,576FITEM,5,-5

22、77FITEM,5,621FITEM,5,-625FITEM,5,707FITEM,5,-711FITEM,5,716FITEM,5,741FITEM,5,-745FITEM,5,750FITEM,5,-751FITEM,5,766FITEM,5,797FITEM,5,-798FITEM,5,854FITEM,5,888FITEM,5,-938FITEM,5,1101FITEM,5,1103FITEM,5,1420FITEM,5,1628FITEM,5,1653FITEM,5,1696FITEM,5,1699FITEM,5,-1702FITEM,5,1726FITEM,5,-1728FITEM

23、,5,1852FITEM,5,-1874FITEM,5,2044FITEM,5,-2066CM,_Y,ELEMESEL,P51XCM,_Y1,ELEMCMSEL,S,_YCMDELE,_YEREF,_Y1,1,0,1,1CMDELE,_Y1ET,2,TARGE169ET,3,CONTA172R,3,R,3,0,0,0.1,10,0,0R,4,R,4,0,0,0.1,10,-0.02,0lsel,s,9lsel,a,5lsel,a,12nsll,s,1type,3real,3esurf,allalls,lsel,s,19lsel,a,20nsll,s,1type,3real,4esurf,all

24、alls,lsel,s,7lsel,a,3lsel,a,11nsll,s,1type,2real,3esurf,allalls,lsel,s,25lsel,a,26nsll,s,1type,2real,4esurf,allalls,FLST,2,2,5,ORDE,2FITEM,2,4FITEM,2,-5DA,P51X,ALL,FLST,2,1,4,ORDE,1FITEM,2,6SFL,P51X,PRES,500,/soluantype,0nlgeom,onoutres,all,allnsubst,200,200,2neqit,1000solve耦合小程序最近用到耦合,写了一段小程序,奉献出来,

25、与大家共享。如果有很多节点，每两个节点位置相同，如果将这些杂乱无章的节点耦合，是件很麻烦的事，可用这段程序，轻松解决。cpnum=0cmsel,s,n-zhong!需要耦合的节点*GET,n_num,NODE,COUNT,!节点总数*do,i,1,n_numcmsel,s,n-zhong*GET,n_lowest,NODE,NUM,MIN,!号码最小的节点*GET,n_x,NODE,n_lowest,LOC,X!该节点坐标*GET,n_y,NODE,n_lowest,LOC,Y*GET,n_z,NODE,n_lowest,LOC,ZNSEL,s,LOC,X,n_x-0.3,n_x+0.3!寻找

26、与该节点位置相同的节点NSEL,R,LOC,Y,n_y-0.3,n_y+0.3NSEL,R,LOC,z,n_z-0.3,n_z+0.3cm,n_cp_cp,node!位置相同的节点形成一个组cmsel,s,n-zhongcmsel,u,n_cp_cpcm,n-zhong,node!取消这些点后剩余的点形成组*GET,n_num_1,NODE,COUNT,!节点总数*if,n_num_1,lt,2,exit!如果节点数小于二则退出cmsel,s,n_cp_cp*GET,n_num,NODE,COUNT,*if,n_num,gt,1,thenCP,cpnum+1,ux,allCP,cpnum+2,

27、uy,allCP,cpnum+3,uz,allcpnum=cpnum+3*else*endif*enddo该段程序可用CPINTF，UX，0.001CPINTF，UY，0.001CPINTF，UZ，0.001代替*DO,I,2,296,3CP,I,UX,I,I+2*ENDDO*DO,I,2,296,3CP,I,UY,I,I+2*ENDDO*DO,I,2,296,3CP,I,UZ,I,I+2*ENDDODK,1,0,UX,UY,UZ,以上几句改为:*DO,I,2,296,3CP,NEXT,ALL,I,I+2*ENDDODK,1,0,ALL或CPINTF,ALL,0.001因为你选用的单元有六个自

28、由度,如果只约束三个,程序是不会运行的.另:三次循环语句的I相等，约束UY时,UX的耦合就被删掉了，最后只剩UZ了这样修改：c*耦合练习/PREP7K,1,0,0K,2,0.1,0L,1,2K,300,0,-10000LGEN,100,1,0.1,2ET,1,BEAM188MP,EX,1,2.1e11MP,PRXY,1,0.3MP,DENS,1,0.783e4SECTYPE,1,BEAM,T,0SECOFFSET,CENTSECDATA,0.06,0.03,0.003,0.006,0,0,0,0,0,0LSEL,ALLLATT,1,1,1,300LESIZE,ALL,1,1,1LMESH,AL

29、Lcpintf,allDK,1,ux,0,UY,UZDK,200,UY,UZACEL,0,9.8,0,FINISH一个流固耦合的例子这个例子关于装有水的水杯旋转，是轴对称问题，为了简化，所以选择了平面模型*SET,RAD,0.8*SET,h,1*SET,g,9.8*SET,OMEGAR,2*SET,ROU,1000/PREP7ET,1,FLUID79KEYOPT,1,3,1MP,EX,1,2E9MP,DENS,1,ROUK,1K,2,RADK,3,RAD,HK,4,HK,4,HA,1,2,3,4LESIZE,ALL,10AMESH,ALLFINISH/SOLDL,2,UXDL,1,UYNSEL

30、,S,LOC,XDSYM,SYMM,XD,ALL,UXD,ALL,UXNSEL,ALLACEL,GOMEGA,OMEGARSOLVEFINISH/POST1SET,LASTPLNSOL,U,X,0,1*SET,UCENT,UY(22)*SET,UEDGE,UY(12)*SET,UELEV,UEDGE-UCENTansys从9.0发展到10.0，一个最大的进步就是流固耦合计算更加规范，这一点已远领先于其他同类软件，实现了单向耦合到即时双向耦合的飞跃，使用户对于解决流固耦合问题又多了一种选择，希望大家对多种方法物理环境转换，fsi,mfx等进行讨论，提供一下案例本人抛砖引玉：使用物理环境法进行流固

31、耦合的实例及讲解流道中有一橡胶垫阻碍水的流动，入口速度为2m/s,其他参数将在命令流中详细给出。求解水通过此流道的压力降，以及稳态条件下橡胶垫的变形。/prep7/sho,gasket,grphshpp,offET,1,141!Fluid-staticmeshET,2,56,!HyperelasticelementFluidStructureInteraction-MultiphysicsDeformationofagasketinaflowfield.!Elementplotsarewrittentothefilegasket.grph.-Waterflowsinaverticalpipet

32、hroughaconstructionformedbyarubbergasket.-DeterminetheequilibriumpositionofthegasketandtheresultingflowfieldTOC o 1-5 h z|Boundaryofmorphingfluid|gasket|Boundaryofmorphingfluid(sf)|!1.Buildthemodeloftheentiredomain:!Fluidregion-staticmesh!GasketleavesaholeinthecenteroftheductMorphingFluidregionisaus

33、erdefinedregionaroundthegasket.Thefluidmeshherewilldeformandbeupdatedasthegasketdeforms.ParameterizeDimensionsintheflowdirection!yent=0.0!Ycoordinateoftheentrancetothepipedyen=1.0!Undeformedgeometryflowentrancelengthysf1=yent+dyen!Ycoordinateofentrancetothemorphingfluidregiondsf1=0.5!Thicknessofupst

34、reamygas=ysf1+dsf1!Ycoordinateofthebottomofthegasketdg=0.02!Thicknessofthegasketdg2=dg/2.ytg=ygas+dg!Ycoordinateoftheinitialtopofthegasketdsf2=0.5!Thicknessofdownstreamregionysf2=ytg+dsf2!YofTopofthedownstreammorphingfluidsregiondyex=6.0!Exitfluidlengthx=0.!LocationoftheaxisymmetricCenterlinedgasr=.

35、20!Initialspanofgasketpiper=0.3!Radiusofthepipexrgap=piper-dgasr!radiusofcompletelyunobtructedflowpassage!Creategeometry!rect,xrgap,piper,ygas,ytg!A1:Gasket(keypoints1-4)rect,x,piper,ysf1,ysf2!A2:Morphingfluidregionrect,x,piper,yent,ysf1!A3:Fluidregionwithstaticmeshrect,x,piper,ysf2,ysf2+dyex!A4:Flu

36、idregionwithstaticmeshaovlap,allk,22,xrgap+dg2,ygas+dg2rarc=dg2*1.1larc,1,4,22,rarcal,6,4adelete,7al,6,3,22,7,8,5,21,1!MeshDivisioninformationngap=10!Numberelementsacrossthegapngas=10!Numberofelementsalongthegasketrgas=-2!Spacingratioalonggasketnflu=ngap+ngas!Numberofelementsacrossthefluidregionrafl

37、u=-3!Spacefluidelementsnearthewallsandcenternenty=8!Elementsalongflow-entranceraent=5!Sizeratiointheinletregionnfl1=20!Elementsalongflow-firstmorph.fluid.nthgas=4!Elementsinthegasketnfl2=3!Elementsalongflow-secondmorph.fluid.next=30!Elementsalongflow-exitregionrext=6!Sizeratioinflowdirectionofoutlet

38、rafls=12!Initialelementspacingratio-morph.fluidlesize,1,ngas,rgaslesize,3,ngas,rgasnfl11=nfl1*2+9lsel,s,2,4,2!(Modifylesizeofline8ifchanginggasketmesh)lesize,all,nthgasallslesize,5,nflu,raflulesize,7,nflu,raflulesize,9,nflu,raflulesize,15,nflu,raflulesize,18,nenty,1./raentlesize,17,nenty,1./raentles

39、ize,21,nfl1,raflslesize,8,nfl11,-1./(rafls+3)lesize,22,nfl1,raflslesize,19,next,rextlesize,20,next,rextAATT,MAT,REAL,TYPE-Settheattributesfortheareasasel,s,1,2aatt,2,2,2!Gasket(material2)asel,s,3cm,area2,areaalist!Listareaselectedforfurthermorphingasel,a,5,6aatt,1,1,1!Fluidarea(material1)allseshape,

40、2asel,u,2,3amesh,alleshape,0asel,s,2,3amesh,all!Createelementplotandwritetothefilegasket.grphasel,s,1,3esla,s/Title,Initialmeshforgasketandneighborhoodeplot/ZOOM,1,RECT,0.3,-0.6,0.4,-0.5alls!CreatePhysicsEnvironmentfortheFluidet,1,141et,2,0!GasketbecomestheNullElementvin=3.5e-1!Inletwatervelocity(me

41、ters/second)!CFDSolutionControlflda,solu,flow,1flda,solu,turb,1flda,iter,exec,400flda,outp,sumf,10!CFDPropertyInformationflda,prot,dens,constantflda,prot,visc,constantflda,nomi,dens,1000.!1000kg/m3fordensity-waterflda,nomi,visc,4.6E-4!4.6E-4kg-s/m(viscosityofwater)flda,conv,pres,1.E-8!Tightenpressur

42、eequationconvergence!CFDBoundaryConditions(AppliedtoSolidModel)lsel,s,8,17,9lsel,a,20dl,all,vx,0.,1!Centerlinesymmetrylsel,s,9dl,all,vx,0.,1dl,all,vy,vin,1lsel,s,2lsel,a,18,19lsel,a,21,22dl,all,vx,0.,1dl,all,vy,0.,1lsel,s,1,3,2lsel,a,6dl,all,vx,0.,1dl,all,vy,0.,1lsel,s,15dl,15,pres,0.,1!InletConditi

43、on!OuterWall!Gasket!Outletpressureconditioncreatenamedcomponentofnodesatthebottomofgasketlsel,s,1nsll,1cm,gasket,nodenlist!Listinitialnodalpositionsofthebottomofthegasket/com,+STARTINGgasketcoordinatesalls/title,FluidAnalysisphysics,write,fluid,fluid!CreatePhysicsEnvironmentfortheStructure!physics,c

44、learet,1,0!TheNullelementforthefluidregionet,2,56!Gasketelement-material2mp,ex,2,2.82E+6!Youngsmodulusforrubbermp,nuxy,2,0.49967!Poissonsratiofortherubbertb,mooney,2tbdata,1,0.293E+6!Mooney-RivlinConstantstbdata,2,0.177E+6!lsel,s,2nsll,1d,all,ux,0.d,all,uy,0.!Fixtheendofthegasketalls/title,structura

45、lanalysisfinish/soluantype,staticnlgeom,oncnvtol,f,-1physics,write,struc,strucphysics,clearsave!Fluid-StructureInteractionLoop!loop=25toler=0.005!Maximumallowednumberofloops!Convergencetoleranceformaximumdisplacement*dim,dismax,array,loop!Definearrayofmaximumdisplacementvalues*dim,strcri,array,loop!

46、Definearrayofconvergencevalues*dim,index,array,loop*do,i,1,loop/soluphysics,read,fluid*if,i,ne,1,thenflda,iter,exec,100*endifsolvefini!Executefluid-structuresolutions!Readinfluidenvironment!Execute100globaliterationsfor!eachnewgeometry!FLOTRANsolution!endoffluidportionphysics,read,struc!Readinstruct

47、uresenvironment/assign,esave,struc,esav!Filesforrestartingnonlinearstructure/assign,emat,struc,emat*if,i,gt,1,thenparsave,allresume!Structuralrestartloop!Saveparametersforconvergencecheck!ResumeDB-toreturnoriginalnodepositionsparresume/prep7!Resumeparametersneededforconvergencecheckantype,stat,restf

48、ini*endif/solusolc,offlsel,s,1,3,2!Selectproperlinestoapplyfluidpressureslsel,a,6nsll,1esel,s,type,2!totheentiregasketsurfaceldread,pres,last,rfl!ApplypressuresurfaceloadfromFlotranallsrescontrol,none!Donotusemultiframerestartfornonlinearsolve*if,i,eq,1,thensave!saveoriginalnodelocationsatthefirstru

49、n*endiffini/post1cmsel,s,gasketnsort,u,sum,1,1*get,dismax(i),sort,0,max!Getthemaximumdisplacementvaluestrcri(i)=toler*dismax(i)allsfini/prep7mkey=2!Selectlevelofmeshmorphingforfluiddamorph,area2,mkey!Performmorphingofmorphingfluid!Createelementplotandwriteitinfilegasket.grphfini/prep7et,1,42asel,s,1

50、,3esla,s/Title,EPLOTafterDAMORPH,area2,%mkey%stepnumber%i%eplotalls!cmsel,s,gasketnlist!Listupdatedcoordinatesofbottomofgasketforcomparison/com,+UPDATEDgasketcoordinatesallsfini/assign,esav/assign,ematCheckingconvergencecriteriaimax=iindex(i)=i*if,i,gt,1,thenstrcri(i)=abs(dismax(i)-dismax(i-1)-toler

51、*dismax(i-1)*if,strcri(i),le,0,thenstrcri(i)=0*exit!Stoploopingifconvergenceisreached*endif*endif*enddoEndoftheComputationalloopsave!NodalcoordinatesofdeformedgeometryaresavedConvergenceprintout*vwrite(/LoopNo.Max.DisplacementStruct.Convergence)/nopr*vlen,imax*vwrite,index(1),dismax(1),strcri(1)(f7.

52、0,2e17.4)finishPostprocessingoftheresults1.Flotranresults.physics,read,fluid/post1set,last/Title,Flotran:StreamlinesNearGasketplnsol,strm/Title,Flotran:PressureContoursplnsol,presfini2.Structuralresults.physics,read,struc/post1set,lastupcoord,-1!Returnoriginalnodepositionschangedbymorphing/Title,Str

53、ucturalresults:vonMisesStressplnsol,s,eqv,1,1fini讲解：橡胶垫在流体作用下发生变形，变形又反过来影响流体形状，例子中设定的流固区，在流体分析和固体分析中都作为分析对象，在结构分析中求解流固区可得到网格的变形，用于流场分析，此区域在流体物理环境中赋予流体属性，在结构物理环境中附于结构属性，这一点是说允许由于橡胶垫变形引起网格变形。纯流体区域仅在流体物理环境中使用，橡胶垫也只在结构物理环境中使用。三个区分别是固体区-橡胶垫；流体区；流固区流体区域编号一定要设为1在创建流体环境时，流体和流固两区分配流体属性，此时固体区，也就是橡胶垫为null,设定好之

54、后将流体物理环境写入物理环境文件。然后清除流体物理环境，定义结构物理环境，此时流体区域为null，定义载荷步和求解选项,写入流体物理环境。最后流/固求解循环！给大家推荐一本讲解流固耦合的书，感觉还不错！张立翔，杨柯.流体结构互动理论及其应用科学出版社。2004.3再给大家推荐一本：居荣初，曾心传。弹性结构与液体的耦联振动理论地震出版社，1983针对液面晃动问题，ANSYS/LS-DYNA提供以下三种方法：1、流固耦合流固耦合是ANSYS/LS-DYNA计算流体和结构间相互作用的最常用的方法，包括单物质+空材料和多物质耦合两大类，流体单元有Euler和ALE两种。其涉及的主要命令如下：*cont

55、rol_ale算法选择有两种2、3,分别为Euler和ale实质上此处二者没有区别，只是因为兼容性进行的设置；两种精度供选择单精度、双精度。*section_solid_ale对单物质+空材料为12号算法，对多物质耦合为11号算法。*ale_multi-material_group进行多物质的定义，最多可以定义20种材料。可以根据物质间能否混合将各种材料定义在不同的材料组ID中。ale_multi-material_system_group该命令决定流体物质的算法（Euler或Ale），或是在运算过程中切换使用两种算法，并可对流体物质进行自由度约束。该命令多与下列三个命令结合使用：ale_mu

56、lti-material_system_curve定义ale系统的运动曲线。ale_multi-material_system_node通过一系列节点定义ale的运动参考坐标系统。ale_multi-material_system_switch定义euler和ale参考系统的切换。上述命令是流体物质涉及的关键字，而我们知道，结构采用Lagrange单元来离散，二者之间的耦合通过下列命令来实现：*constrained_lagrange_in_solid耦合算法分为两种：罚耦合和运动约束。前者遵循能量守恒，后者遵循动量守恒。一般令结构网格较流体网格密以保证界面不出现渗透，否则可以增大NQUAD参

57、数值来增加耦合点，如设置该值为4或5。在970中,此命令第三行又增加了一个控制字ILEAK0，1或2，一般可设置为1。最后给出一个典型算例水箱跌落的部分关键字：*KEYWORD*TITLEboxwater2.k:droppingawaterboxontoarigidplatform$=$1EXECUTIONCONTROLS$=*CONTROL_TERMINATION$ENDTIMENDCYCDTMINENDENGENDMAS0.050000000.000000000.0000000*CONTROL_TIMESTEP$DTINITTSSFACISDOTSLIMTDT2MSLCTMERODEMS1

58、ST0.00000000.200000000.00000000.0000000000*CONTROL_ENERGY$HGENRWENSLNTENRYLEN222$=$3OUTPUTCONTROLS$=*DATABASE_BINARY_D3PLOT$DTCYCLLCDTBEAM0.00050000*DATABASE_GLSTAT0.0001000$=$5|SECTIONS|PARTS|DEFs$=*PARTwaterinthebox$PIDSECIDMIDEOSIDHGIDGRAVADPOPTTMID1110000*SECTION_SOLID_ALE$SECIDELFORMAET12$AFACB

59、FACCFACDFACSTARTENDAAFAC0.00000000.00000000.00000000.00000000.00000000.0000000$*MAT_NULL$MIDRHOPCMUTERODCERODYMPR1000.0000-1.000+100.00000000.00000000.00000000.00000000.0000000*EOS_LINEAR_POLYNOMIAL$EOSIDC0C1C2C3C4C5C60.00000001.50000+90.00000000.00000000.00000000.00000000.0000000$E0V00.00000001.000

60、0000$=*PARTvoidportioninthebox1110000*INITIAL_VOID_PART2$=*PARTrigidboxcontainingwater$PIDSECIDMIDEOSIDHGIDGRAVADPOPTTMID3300000*SECTION_SOLID$SECIDELFORMAET0*MAT_RIGID32000.00001.00000+80.00000000.00000000.00000000.00000000.00000000.00000000.00000000.00000000.00000000.00000000.00000000.00000000.000