ICEMCFDDDN介绍

3/13/2023DDN 1ICEM DDNICEM DDN介绍介绍3/13/2023DDN 2ICEM DDNICEM DDN介绍介绍lDDN是什么?lDDN相关的工具lDDN的用法l示例实践-2-D管道交界处点，线和圆弧-3-D管道交界处在曲面上处理-风扇罩读入和清理IGES文件3/13/2023DDN 3DDNDDN是什么是什么?lDDN是一个功能齐全的3-D CAD系统-如同其它的CAD软件包，DDN所包含的功能是无法在一天之内都学会的lDDN支持设计/制图/数值控制lDDN是ICEM CFD的历史基础-ICEM CFD Mulcad完全运行在DDN中l过去，DDN是进入ICEM CFD的唯一路径-所有的几何图形都要读入到DDN中l现在已经让位于直接的CAD界面lUpcoming tools with continue move away from DDN-IGES-Tetin-Easy CAD in Mesh Editor3/13/2023DDN 4在在ICEM CFDICEM CFD中，中，DDNDDN适合哪些情况适合哪些情况?l为没有CAD软件包的用户提供CAD设计l提供CAD的读入和清理-IGES，VDA，DXF translators create DDN part file-通过输入读入点数据l从DDN CAD数据中创建tetin文件3/13/2023DDN 5DDNDDN工具工具l在ICEM CFD图形用户界面，几何图形菜单，DDN工具开始-DDN-DDN-tetin DDN mesher interface Direct CAD interface for DDN-Comak 参数化几何图形创建工具-输入 读入到DDN的点数据-Frontal Frontal area calculations3/13/2023DDN 6DDN DDN 例子例子1 12-D 管道交界3/13/2023DDN 7DDNDDN例子例子12-D12-D管道交界管道交界l标题介绍-打开新的DDN part-DDN屏幕布局-使用DDN功能按钮和菜单-鼠标使用-创建点，线和圆弧-Trimming 2-D curves-Saving the part3/13/2023DDN 8打开新的工程（打开新的工程（ProjectProject）l从打开新的（空的）工程开始-选择菜单：File Open-保存并关闭你所打开的任何工程-输入工程名“DDN_ex1”3/13/2023DDN 9运行运行DDNDDNl选择菜单：Geometry DDN Tools DDNl输入新的零件名（2dpipes）然后点击Accept-Left list is common to all projects in working directory-Right list is for current project(your list should be empty)Enter new part name here3/13/2023DDN 10使用使用DDNDDN屏幕布局屏幕布局Information bar功能按钮Summary help pages菜单/对话窗口Interrupt bar主要视图区域3/13/2023DDN 11使用使用DDNDDN功能图标功能图标l鼠标左键选择图标l选择“?”图标获取功能的简单描述Select here for point creation tabletSelect here to activate function description tags3/13/2023DDN 12菜单菜单/对话窗口对话窗口l用F1键改变菜单显示模式-Display off,with border,without border,with border and backgroundl菜单和子菜单可以进入所有的DDN功能-用鼠标在菜单中选择-按下数字键 1-9,0对应10 Shift-1对应11l注意菜单区域的提示注意菜单区域的提示Root Menu3/13/2023DDN 13例子例子从菜单创建点从菜单创建点l选择9,2从坐标系中创建点3/13/2023DDN 14例子例子Point Creation from TabletPoint Creation from TabletlCan also select the same function using the tabletl在很多情况下，数据是在菜单/对话区域输入的首先点击这里在菜单/对话区域输入点的坐标然后这里3/13/2023DDN 15鼠标用法鼠标用法选择模式选择模式l在默认的情况下，用户是在选择模式下-左键 Select functions from tablet and menu 在屏幕上选择实体-中键 操作完成（点击按钮）Operation reject(click,then release while moving left)-右键 Options(differ depending on function)Used often at prompt select entity to change manner of selection3/13/2023DDN 162-D 2-D 管道交界管道交界l2-D几何图形创建-点，线和圆弧-Trimming 2-D curves3/13/2023DDN 17创建点创建点l选择点图标，然后xyz图标-在菜单中输入点-报告当前的x，y和z的值-Press enter to move from x to y value-Press enter to move from y to z value-点击鼠标中键创建点首先点击这里然后这里在菜单对话区域输入点的坐标3/13/2023DDN 18创建点创建点l创建如下点：-0,0,0-0,16,0-48,64,0-64,64,0-52,-4,0-56,-4,0lChoose scale to fit icon,then zoom outScale to fitMiddle-click here to zoom out3/13/2023DDN 19创建点之后创建点之后 3/13/2023DDN 20创建线创建线l创建水平和垂直构造线Create horizontal and vertical construction lines-Select Line Horiz Change point mode to existing point Create three horizontal lines-Then select Line Vert Create five vertical lines-Lines extend to display limitsLineChange point selection to existing point3/13/2023DDN 21创建线之后创建线之后3/13/2023DDN 22Trimming 2-D CurvesTrimming 2-D CurveslUse trim functions to trim construction curves-Use trim curves at intersection optionTrim at int.Select at these four locations3/13/2023DDN 23增加圆弧增加圆弧lAdd arcs as filletslChoose option to trim,autoselect,indicate center-输入半径16-Select fillet location as shown-Repeat for radius of 32Click here for 16 rad.filletClick here for 32 rad.fillet3/13/2023DDN 24Additional LineAdditional LinelCreate line for end of small ductl在已有的两个点之间Click here and here3/13/2023DDN 25Final TrimsFinal TrimslTrim vertical lines at 32 radius fillet-Use trim at a curve3/13/2023DDN 26显示的公差显示的公差l所画出的圆弧是一系列直线构成的-增加公差提高显示的能力-减少公差提高显示质量l设定显示公差为0.01lPress Ctrl-R to regenerate display3/13/2023DDN 27保存零件保存零件l选择菜单：File Save,Quitl一定要注意你选择的位置！Click hereNot here!3/13/2023DDN 28DDNDDN例子例子11总结总结lTopics introduced-打开新的DDN零件-DDN屏幕布局-使用DDN函数和菜单-鼠标的用法-创建点、线和圆弧-Trimming 2-D curves-保存零件3/13/2023DDN 29DDNDDN例子例子2 23-D管道交界3/13/2023DDN 30DDN Example 2 3-D Pipe DDN Example 2 3-D Pipe IntersectionIntersectionlTopics introduced-Drawing units-Manipulating the part orientation(dynamic mode)-Creation of surfaces-Converting surfaces to B-Spline-Creating intersection curves-Trimming surfaces-Extracting trim surface bounding curves3/13/2023DDN 31零件尺寸零件尺寸100150100403/13/2023DDN 32打开新的工程打开新的工程lStart by opening a new(empty)project-Select File Open-Save and close any projects you have open-Enter the project name DDN_ex23/13/2023DDN 33Create Part and Set Drawing UnitsCreate Part and Set Drawing UnitslSelect DDN Tools DDNl输入零件名3dpipes然后点击Acceptl设定绘图单位为毫米-DDN的单位为英寸或毫米-Used only to set tolerance valuesClick here to toggle between inches and mm3/13/2023DDN 34创建点创建点l在如下位置创建点：-0,0,0-0,100,0-0,0,150lCreate lines between those points to form the axes of the two cylinders-First we need to find the points!3/13/2023DDN 35动态模式动态模式lTo manipulate the displayed objects,change to Dynamic Mode,using one of the methods below:-Press F9 key-Select from tablet,near bottom of screen-Press and release right(or left)button while holding the middle mouse buttonyes this sounds crazy,but its actually useful!Click here3/13/2023DDN 36鼠标用法鼠标用法动态模式动态模式lWhile in dynamic mode,icon shown is displayedl鼠标：-左键 Click and drag for 3-D rotation-中键 Click and drag to translate-右键 Click and drag up to zoom in Click and drag down to zoom outDynamic mode icon3/13/2023DDN 37动态旋转选项动态旋转选项lRotate about select entity-Click on entity and drag while holding left buttonlRestricted rotation modes-About screen x-axis Click inside horizontal arrowhead and drag-About screen y-zaxis Click inside horizontal arrowhead and drag-About screen z-axis Click between squares(region shown in black at right)and drag Screen X rotationScreen Y rotationScreen Z rotation3/13/2023DDN 38动态旋转模式动态旋转模式lClick on the straight-lines of the dynamic icon to change the rotation modelThere are three modes-Default Used almost exclusively-Animated-StepwiselDynamic icon changes to indicate modeClick here to change modeDefaultAnimatedStepwise3/13/2023DDN 39Achieving the Desired ViewAchieving the Desired ViewlExperiment with orienting the view with the mouse in Dynamic modelOnce you are comfortable,orient the view so you can see all three points and we will continue with Example#23/13/2023DDN 40创建线创建线lCreate lines for the axes of the two cylinders by selecting existing points,as shown3/13/2023DDN 41Workplane IconWorkplane IconlNote workplane icon-Flat,filled arrow indicates X-axis-Flat,open arrow indicates Y-axis-Three-point arrow indicates Z-axisXYZ3/13/2023DDN 42创建圆柱创建圆柱lCreate two half-cylinders for each pipelSelect surface icon,then cylinderlIn menu,-Select 1.AXIS-Select 1.EXISTING LINE3/13/2023DDN 43创建圆柱创建圆柱-At prompt INDICATE LINE,select line aligned with Y-axisClick here3/13/2023DDN 44创建圆柱创建圆柱-For RADIUS,enter 20-For STARTING ANGLE,enter 0-For ENDING ANGLE,enter 1803/13/2023DDN 45创建第二个圆柱创建第二个圆柱lRepeat the process for the second cylinder-Select AXIS,EXISTING LINE-Select line aligned with X-axis-Enter 50,0,180 for RADIUS,STARTING ANGLE and ENDING ANGLE3/13/2023DDN 46转换曲面类型转换曲面类型l在ICEM CFD中，所有用于划分网格的曲面必须是B-样条曲面lBefore converting surfaces,examine the advanced design modals-Select surface function,then MODES to display the following menu3/13/2023DDN 47Advanced Design ModalsAdvanced Design ModalslFor conversion of surfaces,set-14.B-SPLINE SEGMENT TYPE to MULTIPLE-18.CONVERSION OLD ENTITY to DELETElFor creation of intersection curve,set-1.CREATED CURVE TYPE to SURFACE CURVE3/13/2023DDN 48将曲面转换为将曲面转换为B-B-样条样条lSelect surface icon,then B-Spline and Convers.-At prompt Select surfaces or solids,select two surfaces displayed-Press middle mouse button to confirm-At prompt Tolerance enter 0.01-Press Enter3/13/2023DDN 49创建交叉曲线创建交叉曲线lSelect 3-D curves icon,then Surf-Surf IntersectlAt prompt First Surface Set-Select one of the surfaces-Press middle button to acceptlAt prompt Second Surface Set-Select one of the surfaces-Press middle button to accept3/13/2023DDN 50创建交叉曲线创建交叉曲线lIntersection curve is createdlSelect 1.EXIT-SAVE CURVES3/13/2023DDN 51在交叉曲线处裁剪曲面在交叉曲线处裁剪曲面lSelect surface icon,then Trimmed icon-Select 1.TRIM SURFACE-At prompt INDICATE SURFACE,pick the larger cylinder-At prompt INDICATE TRIM CURVES,pick the intersection curve Press middle mouse button to accept 3/13/2023DDN 52在交叉曲线处裁剪曲面在交叉曲线处裁剪曲面-For ACTIVE REGIONS,select 1.SCREEN POSITION-Click on surface(in the middle of the surface)on the side to keepClick on side to keep3/13/2023DDN 53裁剪第二个圆柱裁剪第二个圆柱lRepeat process for second cylinderlAfter trimming:3/13/2023DDN 54完成模型完成模型lFor meshing in Hexa and Tetra,we would want to create an enclosed surface model,and create required curves and pointslTo do this we would:-Extract bounding curves for all surfaces-Create additional curves as required-Create additional surfaces from bounding curves-Extract points at key locations(i.e.at corners)lFor now,we will save and exit this example3/13/2023DDN 55保存零件保存零件lSelect File Save,QuitlBe careful where you select!Click hereNot here!3/13/2023DDN 56DDNDDN例子例子22总结总结lTopics introduced-Drawing units-Manipulating the part orientation(dynamic mode)-Creation of surfaces-Converting surfaces to B-Spline-Creating intersection curves-Trimming surfaces-Extracting trim surface bounding curves3/13/2023DDN 57DDN DDN 例子例子3 3风扇罩3/13/2023DDN 58DDN Example 3 Fan HousingDDN Example 3 Fan HousinglTopics introduced-Converting IGES parts to DDN-Using levels in DDN-Extracting trim surface bounding curves-Creating additional surfaces3/13/2023DDN 59Create a New ProjectCreate a New ProjectlSelect File Open-When prompted,Close your exiting project-In Select Project menu,enter name:fan_housing-Press Accept3/13/2023DDN 60Importing IGES Files to DDNImporting IGES Files to DDNlSelect File Import Geo IGES-DDNlSelect file volute.igs using lPress Accept in the IGES-DDN window3/13/2023DDN 61Examining the Part in DDNExamining the Part in DDNlSelect Geometry DDN Tools DDNlSelect the volute part from the project parts listlIn DDN,orient the part using Scale to Fit icon and dynamic mode3/13/2023DDN 62Using Levels in DDNUsing Levels in DDNlLevels are a convenient way of dealing with subsets of complex parts-In DDN,valid levels are integers from 0 to 1023lFollowing,we will illustrate-Changing color mode to color by level-Changing the active level-Modifying the level of existing entities-Blanking and unblanking by level3/13/2023DDN 63改变颜色模式改变颜色模式lColor mode can toggle between color by:-Type:-Pen Number:-Level:-Color:lClick icon as shown until stairsteps are shown-Entities will be colored by their level-Initially all entities will be white(on level 0)Click here 3/13/2023DDN 64Changing the Active LevelChanging the Active LevellNew entities created will be placed on active levellChange level by clicking on level icon,as shown-Left button:increment level-Middle button:decrement level-Right button:specify levelClick here 3/13/2023DDN 65Modifying the Level of EntitiesModifying the Level of EntitieslTo change the level of an existing entity-Select Mod Prp from the Interrupt Bar-From the menu,select 1.Level-Enter the level to change to(for now,enter 10)-Press middle mouse button to continue modify operation-Select entities on screen-Press middle mouse button to complete modify-Entities will be moved to level 10(colored blue)3/13/2023DDN 66Other Selection MethodsOther Selection MethodslUntil now,we have only been selecting individual entitieslMany selection methods can be used:-At a prompt such as select entity press the e key to list selection options menu,or Select the select options icon3/13/2023DDN 67Modifying LevelsModifying LevelslUsing this method:-Assign outside surfaces to level 10-Assign inside surfaces to level 1lUltimately,the goal is to group the surfaces which are relevant to CFD on level 1lWe could delete surfaces,but moving them to another level is saferlUse Blank and Unblank to help clarify which objects are on what level3/13/2023DDN 68Blanking/Unblanking by LevelBlanking/Unblanking by LevellSelect the blank iconlExperiment with blank and unblank level rangelContinue placing entities on desired levels3/13/2023DDN 69Inside SurfacesInside SurfaceslOnce complete,blank level 10 and unblank level 1 to display inside surfaces3/13/2023DDN 70Extracting Bounding CurvesExtracting Bounding CurveslTrim curves exist for all trim surface boundarieslHowever,ICEM needs free-standing curves(i.e.independent from surfaces)for meshing in Tetra and HexalThese can be created using the translate and copy functionlThis procedure is described on our web site:lHere we will present the abridged version3/13/2023DDN 71Extracting Bounding CurvesExtracting Bounding CurveslThe abridged recipe for copying bounding curves:-F-this goes to top of menu structure-13-shift-3,entity manipulation-8-duplicate and translate-E-to access entity selection options-0-to define constraints-4-to select by type-2-to select all 3-D curves-op complete(middle mouse click)-op complete(middle mouse click)-4-select all displayed-op complete(middle mouse click)3/13/2023DDN 72Extracting Bounding CurvesExtracting Bounding CurveslThis completes selection of bounding curves,nowlWe want to specify a zero translation distance-Select xyz to enter coordinates-Enter the same coordinate set twice(eg.0,0,0)-This completes the processlTo confirm:-Blank all displayed surfaces-Press r to repaint the screen3/13/2023DDN 73Blanking All Displayed SurfacesBlanking All Displayed SurfaceslTo blank all displayed surfaces-Select blank function-Under blank,select surface icon-In menu,select 4.ALL DISPLAYEDlNow you should see only curves for the inside surfaces-As before,use Mod Prp to put those curves on level 23/13/2023DDN 74A Note About Extracted CurvesA Note About Extracted CurveslCurves will be extracted on every edge of every surfacelWhere two surfaces meet,there will be duplicate curves,one extracted from each adjacent surfacelThis is not necessarily a problem,but it can cause confusion later in the meshing process3/13/2023DDN 75Saving Your WorkSaving Your WorklIts a good idea to save frequently,-Choose,-Click on File,Go On3/13/2023DDN 76重命名零件重命名零件lTo save the part under a different name:-Click on the name near the bottom,left of the screen-Enter a new name-Subsequent saves will be saved to the new nameClick here 3/13/2023DDN 77Creating Additional SurfacesCreating Additional SurfaceslCreate surfaces representing the inlet and outletlEasiest method is create B-spline surfaces from bounding curves-Bounding curves have already been extractedlBlank entire part and unblank level 2(curves)lChange active level to level 3,so new entities will be on a unique level3/13/2023DDN 78B-Spline Surf from Bounding CurvesB-Spline Surf from Bounding CurveslSelect Surface IconlSelect B-SplinelSelect icon for from four bounding curves,as shown:3/13/2023DDN 79Creating Outlet SurfacesCreating Outlet SurfaceslFor first surface,select three curves as shown3/13/2023DDN 80Creating Outlet SurfacesCreating Outlet SurfaceslPress middle button twice to complete creation of first surfacelRepeat process to create two more surfaces at outletOne outlet surface Outlet surfaces complete3/13/2023DDN 81Creating Inlet SurfacesCreating Inlet SurfaceslProcess is similar for inlet surfaceslPick two opposite curves-Pick near same end or resulting surface will be twistedlThis creates half of the inletlRepeat process for opposite halfClick here and here 3/13/2023DDN 82完整的几何图形完整的几何图形lBlank the entire part and unblank the following levels:-1 inside surfaces of the fan housing-2 curves-3 surfaces for the inlet and outletlSave the part and exit3/13/2023DDN 83DDNDDN例子例子33总结总结lTopics introduced-Converting IGES parts to DDN-Using levels in DDN-Extracting trim surface bounding curves-Creating additional surfaces3/13/2023DDN 84DDN-Tetin ExampleDDN-Tetin ExamplelThis is a program which runs on top of DDN(GPL program)lProcess follows family creation and assignment like weve done using the Mesh EditorlCreate familieslAssign geometric entities to familieslAssign mesh size information to families and curveslFor the new user,it may be easier to perform many of these operations in the Mesh Editor3/13/2023DDN 85Creating FamiliesCreating FamilieslSelect Family,Add-Type name of families to add-Press the enter key to add family-Press middle mouse when donelEntity Add-Select family to receive entities-Select entities,press middle mouse when done-Assign size information(or accept defaults and use Mesher Interface)3/13/2023DDN 86Blank/Unblank FamiliesBlank/Unblank FamilieslUse Family,Blank/Unblank-As you work,choose Blank All,All entities to blank all the entities which have been assigned to families-Continue assigning entities to families until all entities have been assignedlUse Family,List-Displays family names and the number of entities assigned to each family-Press R to reset display and see your geometry after reviewing listlSave the Tetin file-Choose File,Save from the DDN-Tetin menu-Dont exit from the DDN tablet!