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实例1：某一潜水艇可以简化为一圆筒，它由三层组成，最外面一层为不锈钢，中间为玻纤隔热层，最里面为铝层，筒内为空气，筒外为海水，求内外壁面温度及温度分布。几何参数：筒外径30feet总壁厚2inch不锈钢层壁厚0.75inch玻纤层壁厚1inch铝层壁厚0.25inch筒长200feet导热系数不锈钢8.27BTU/hr.ft.oF玻纤0.028BTU/hr.ft.oF铝117.4BTU/hr.ft.oF边界条件空气温度70oF海水温度44.5oF空气对流系数2.5BTU/hr.ft2.oF海水对流系数80BTU/hr.ft2.oF沿垂直于圆筒轴线作横截面，得到一圆环，取其中1度进行分析,如图示。不锈钢玻璃纤维铝R15feet海水空气以下分别列出log文件和菜单文件。/filename,Steady1/title,Steady-statethermalanalysisofsubmarine/units,BFTRo=15!外径(ft)Rss=15-(0.75/12)!不锈钢层内径ft)Rins=15-(1.75/12)!玻璃纤维层内径(ft)Ral=15-(2/12)!铝层内径(ft)Tair=70!潜水艇内空气温度Tsea=44.5!海水温度Kss=8.27!不锈钢的导热系数(BTU/hr.ft.oF)Kins=0.028!玻璃纤维的导热系数(BTU/hr.ft.oF)Kal=117.4!铝的导热系数(BTU/hr.ft.oF)Hair=2.5!空气的对流系数(BTU/hr.ft2.oF)Hsea=80!海水的对流系数(BTU/hr.ft2.oF)/prep7et,1,plane55!定义二维热单元mp,kxx,1,Kss!设定不锈钢的导热系数mp,kxx,2,Kins!设定玻璃纤维的导热系数mp,kxx,3,Kal!设定铝的导热系数pcirc,Ro,Rss,-0.5,0.5!创建几何模型pcirc,Rss,Rins,-0.5,0.5pcirc,Rins,Ral,-0.5,0.5aglue,allnumcmp,arealesize,1,,,16!设定划分网格密度lesize,4,,,4lesize,14,,,5lesize,16,,,2eshape,2!设定为映射网格划分mat,1amesh,1mat,2amesh,2mat,3amesh,3/SOLUSFL,11,CONV,HAIR,,TAIR!施加空气对流边界SFL,1,CONV,HSEA,,TSEA!施加海水对流边界SOLVE/POST1PLNSOL！输出温度彩色云图finish菜单操作:1.UtilityMenuFilechangejobename,输入Steady1；2.UtilityMenuFilechangetitle,输入Steady-statethermalanalysisofsubmarine；3.在命令行输入:/units,BFT；4.MainMenu:Preprocessor；5.MainMenu:PreprocessorElementTypeAdd/Edit/Delete,选择PLANE55；6.MainMenu:PreprocessorMaterialProp-Constant-Isotropic,默认材料编号为1,在KXX框中输入8.27,选择APPLY,输入材料编号为2,在KXX框中输入0.028,选择APPLY,输入材料编号为3,在KXX框中输入117.4；7.MainMenu:Preprocessor-Modeling-Create-Areas-CircleByDimensions,在RAD1中输入15,在RAD2中输入15-(.75/12),在THERA1中输入-0.5,在THERA2中输入0.5,选择APPLY,在RAD1中输入15-(.75/12),在RAD2中输入15-(1.75/12),选择APPLY,在RAD1中输入15-(1.75/12),在RAD2中输入15-2/12,选择OK；8.MainMenu:Preprocessor-Modeling-Operate-Booleane-GlueArea,选择PICKALL；9.MainMenu:Preprocessor-Meshing-SizeContrls-Lines-PickedLines,选择不锈钢层短边,在NDIV框中输入4,选择APPLY,选择玻璃纤维层的短边,在NDIV框中输入5,选择APPLY,选择铝层的短边,在NDIV框中输入2,选择APPLY,选择四个长边,在NDIV中输入16；10.MainMenu:Preprocessor-Attributes-DefinePickedArea,选择不锈钢层,在MAT框中输入1,选择APPLY,选择玻璃纤维层,在MAT框中输入2,选择APPLY,选择铝层,在MAT框中输入3,选择OK；11.MainMenu:Preprocessor-Meshing-Mesh-Areas-Mapped3or4sided,选择PICKALL；12.MainMenu:Solution-Loads-Apply-Thermal-ConvectionOnlines,选择不锈钢外壁,在VALI框中输入80,在VAL2I框中输入44.5,选择APPLY,选择铝层内壁,在VALI框中输入2.5,在VAL2I框中输入70,选择OK；13.MainMenu:Solution-Solve-CurrentLS；14.MainMenu:GeneralPostprocPlotResults-ContourPlot-NodalSolu,选择Temperature。对流换热系数定义：流体与固体表面之间的换热能力，比如说，物体表面与附近空气温差1℃，单位时间单位面积上通过对流与附近空气交换的热量。单位为W/(m^2·℃)。表面对流换热系数的数值与换热过程中流体的物理性质、换热表面的形状、部位、表面与流体之间的温差以及流体的流速等都有密切关系。物体表面附近的流体的流速愈大，其表面对流换热系数也愈大。如人处在风速较大的环境中，由于皮肤表面的对流换热系数较大，其散热（或吸热）量也较大。对流换热系数可用经验公式计算，通常用巴兹公式计算。的大致量级：空气自然对流5～25，气体强制对流20～100。实例2:一钢铸件及其砂模的横截面尺寸如图所示:砂模的热物理性能如下表所示:单位制导热系数(KXX)Btu/hr.in.oF0.025密度(DENS)lbm/in30.254比热(C)Btu/lbm.oF0.28铸钢的热物理性能如下表所示:单位制0oF2643oF2750oF2875oF导热系数Btu/hr.in.oF1.441.541.221.22焓Btu/in30128.1163.8174.2初始条件:铸钢的温度为2875oF，砂模的温度为80oF；砂模外边界的对流边界条件：对流系数0.014Btu/hr.in2.oF，空气温度80oF；求3个小时后铸钢及砂模的温度分布。/Title,CastingSolidification!进入前处理/prep7et,1,plane55！定义单元mp,dens,1,0.254！定义砂模热性能mp,kxx,1,0.025mp,c,1,0.28mptemp,1,0,2643,2750,2875！定义铸钢的热性能mpdata,kxx,2,1.44,1.54,1.22,1.22mpdata,enth,2,0,128.1,163.8,174.2mpplot,kxx,2mpplot,enth,2save！创建几何模型k,1,0,0,0k,2,22,0,0k,3,10,12,0k,4,0,12,0/pnum,kp,1/pnum,line,1/pnum,area,1/Triad,ltopkplota,1,2,3,4saverectng,4,22,4,8aplotaovlap,alladele,3aplotsave！划分网格esize,1amesh,5mat,2aplotamesh,4eplot/pnum,elem/number,1save！进入加载求解/SOLUantype,trans！设定为瞬态分析esel,s,mat,,2！设定铸钢的初始温度nsle,s/replotic,all,temp,2875esel,inve！设定砂模的初始温度nsle,s/replotic,all,temp,80allselsavelplotsfl,1,CONV,0.014,,80！设定砂模外边界对流sfl,3,CONV,0.014,,80sfl,4,CONV,0.014,,80/psf,conv,2time,3！设定瞬态分析时间kbc,1！设定为阶越的载荷autots,on！打开自动时间步长deltim,0.01,0.001,0.25！设定时间步长timint,on！打开时间积分tintp,,,,1！将THETA设定为1outres,all,all！输入每个子步的结果solve！进入后处理/post26/pnum,node,1/number,0eplotnsol,2,204,temp,center！设定铸钢中心点温度随时间的变量plvar,2！绘制温度～时间曲线savefinish菜单操作:1.UtilityMenuFileChangeTitle,输入CastingSolidification;2.定义单元类型:MainMenuPreprocessorElementTypeAdd/Edit/Delete,Add,Quad4node55；3.定义砂模热性能:MainMenuPreprocessorMaterialPropsIsotropic,默认材料编号1,在Density(DENS)框中输入0.054,在Thermalconductivity(KXX)框中输入0.025,在Specificheat(C)框中输入0.28;4.定义铸钢热性能温度表:MainMenuPreprocessorMaterialProps-TempDependent-TempTable,输入T1=0,T2=2643,T3=2750,T4=2875;5.定义铸钢热性能:MainMenuPreprocessorMaterialProps-TempDependent-PropTable,选择ThConductivity,选择KXX,输入材料编号2,输入C1=1.44,C2=1.54,C3=1.22,C4=1.22,选择Apply,选择Enthalpy,输入C1=0,C2=128.1,C3=163.8,C4=174.2;6.创建关键点:MainMenuPreprocessor-Modeling-CreateKeypointsInActiveCS,输入关键点编号1,输入坐标0,0,0,输入关键点编号2,输入坐标22,0,0,输入关键点编号3,输入坐标10,12,0,输入关键点编号4,输入坐标0,12,0;7.创建几何模型:MainMenuPreprocessor-Modeling-Create-Areas-ArbitraryThroughKPs,顺序选取关键点1,2,3,4;8.MainMenuPreprocessor-Modeling-Create-Areas-RectangleByDimension,输入X1=4,X2=22,Y1=4,Y2=8;9.进行布尔操作:MainMenuPreprocessor-Modeling-Operate-Booleans-OverlapArea,Pickall；10.删除多余面:MainMenuPreprocessor-Modeling-DeleteAreaandBelow,311.保存数据库:在AnsysToolbar中选取SAVE_DB;12.定义单元大小:MainMenuPreprocessor-Meshing-SizeC