SOLID GEOMETRY CREATION AND EDITING 
          
         Even though not needed for geometry creation and editing, you may specify the User Profile 
         OptiStruct right at the beginning of your session. Simply click on:  
          
          
         In this section of the tutorial you will learn more about solid geometry creation and editing i.e. how 
         to convert a CAD surface model into a solid (volume) model. 
          
         Load the HyperMesh binary file named: monitor_bracket_surfs.hm 
          
          
          
          
          
          
          
          
          
          
          
         Activate the shaded surface display mode:  
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
                         The loaded geometry consists of surfaces only. 
          
                  
                  
                  
                                                                    
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         Build solid geometry based on surfaces 
         The imported geometry is based on lines and surface, only. Provided the surfaces form a closed 
         volume, a geometry solid can be easily created as shown in the next step. 
          
         GeometryCreateSolids Bounding Surfaces 
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
         select one surface (which in turn will automatically select all other surfaces) and create 1 solid. 
         In the display mode Mixed          the geometry solid is shown as: 
                                              
                                              
                                              
                                              
                                              
                                              
                                              
                                              
                                              
                                              
                                              
                                              
                                              
                                              
                                             Note: the geometry consists of 1 solid  
                                                                    
                                      3 
          
                                                                    
                                                                    
          
         To obtain better solid mesh control the solid will be partitioned. 
         First, the geometry display mode is set to ‘Mappable’: 
          
         As indicated in the image below, different colors are assigned to solids, depending whether the solids 
         are fully partitioned (=Full partition faces) or only partly (Fin faces) etc. Especially helpful with respect 
         to hexahedral meshing are the colors related to the “Mappable display mode” (see 
         PreferencesColors). 
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
                                                   The color coding informs 
                                                   you that hexa-meshing of 
                                                   this geometry/solid is not 
                                                   possible i.e. the solid is not 
                                                   ‘Mappable’.  
                                                   Note: Tetrameshing does 
                                                   not need mappable solids. 
          
          
          
                                                                    
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         Even though meshing will be based on tetrahedral elements, we are going to partition the solid into 
         multiple solids next. In this way the element edges/faces will align with the boundaries of the 
         individual solids. 
                  
         GeometryEditSolidsTrim with Lines 
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
         In order to trim off the cylinder, the option “trim with bounding lines” is being used 
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
                                                                    
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