2D6 Meshing a Model Using Shrink Wrap.docx

1、2D6 Meshing a Model Using Shrink WrapNavigation: HyperMesh HyperMesh Tutorials Meshing 2-D ElementsMeshing a Model Using Shrink Wrap - HM-3150 In this tutorial you will learn how to:Mesh a component using the loose shell shrink wrap.Mesh a component using the tight shell shrink wrap.Mesh a component

2、 using the tight solid shrink wrap.The Shrink Wrap tool can be used to generate an enclosed volume or solid mesh, and is typically used to approximate and simplify an existing model.Exercise: Meshing a Model Using Shrink WrapYou can shrink wrap elements, components, surfaces, or solids.The shrink wr

3、ap allows for wrapping of multiple components if they are selected.The selection provides the option to wrap all elements, components, surfaces or solids, or only a certain portion of the model if desired. The input to the shrink wrap (that is, the model parts that you wish to wrap) can consist of 2

4、-D or 3-D elements along with surfaces or solids.The shrink wrap is able to stitch over very bad geometry to generate an enclosed volume mesh for tetra-meshing. The shrink wrap tool can work from elements (whether 2-D or 3-D) or geometry. Thus, in the case of an unclean geometry model with many rele

5、ased (free) edges, you can either generate any arbitrary mesh on the unclean geometry using the automesh functionality beforehand and then create shrink wrap or you can simply select the surface or solid without meshing the geometry first; either of these steps will yield good output mesh. (The key

6、in such cases is to ensure that the element size used for the shrink wrap is large enough to stitch over the unclean surface edge splits so that an enclosed volume can be created.)The element size affects the ability of the shrink wrap to follow the geometry of the model. The larger the element size

7、, the more simplified the model will appear. With a smaller element size the shrink wrap will more closely follow the model. The jacobian value for the solid mesh follows the same type of pattern. As the jacobian value gets smaller the shrink wrap more closely follows the profile of the model. Note

8、that the smaller the jacobian value, the longer it takes to generate the mesh. Shrink wrap mesh can be generated as a surface mesh, or as a full-volume hex mesh, by use of the shrink wrap panel. The distinction between surface or volume mesh is an option labeled generate solid mesh.This tutorial use

9、s the model called shrinkwrap.hm in the tutorialshm folder.Step 1: Open the model shrinkwrap.hm.Step 2: Create a loose shell shrink wrap mesh in the loose_gap component.1.Click Shaded Geometry and Surface Edges if the model is not shaded already.2.Review the surface geometry on the screen. Notice th

10、e gap in the geometry.3.Click Mesh, then Create, then Shrink Wrap Mesh.4.Make sure the loose sub-panel is active.5.Select the component in the graphics area.6.For element size, enter 4. 7.Click mesh to create the shrink wrap.8.Expand the Component folder in the Model browser. 9.Hide the surfaces com

11、ponent in the Model browser.10.Click return to exit the panel.Step 3: Review the solid geometry.1.Show the block component in the Model browser.2.Review the model to see the features.3.Hide the block component in the Model browser.Step 4: Create a loose shell shrink wrap mesh in the loose component.

12、1.Hide the loose_gap component in the Model browser.2.Right-click the loose component and click Make Current.3.From the Mesh menu, click Create, then Shrink Wrap Mesh.4.Activate the loose sub-panel if not already done.5.Click comps and select block from the component list.6.For the element size, ent

13、er 10.7.Click mesh to create the mesh.8.Click reject to reject the mesh.9.Change the element size to 5.10.Click reject to reject the mesh.11.Change the element size to 3.12.Click mesh to create the mesh.The shrink wrap mesh with the geometry hidden13. Click reject to reject the mesh.Step 5: Create a

14、 tight shell shrink wrap in the tight_shell component.1.Hide the loose component using the Model browser.2.Right-click tight_shell and click Make Current.3.Activate the tight sub-panel in the Shrink Wrap panel.4.Click comps and select the block component.5.Make sure the element size is set to 3.6.Cl

15、ick mesh to create the mesh.Step 6: Create a tight solid shrink wrap in the tight_solid component1.Hide the tight_shell component in the Model browser.2.Right-click the tight_solid component in the Model browser and click Make Current.3.Activate the generate solid mesh option.4.Click comps and selec

16、t the block component.5.Change the minimum jacobian to 1.6.Click mesh to create the mesh.7.Click reject to reject the mesh.8.Change the minimum jacobian to 0.7.9.Click mesh to create the shrinkwrap.10.Click to open the Mask panel.11.If not already set, set the panel collector to elems.12.Use SHIFT +

17、 left mouse button to select a group of elements.13.Click mask to mask the elements.14.Click return to exit the panel.Step 7 (Optional): Change the minimum jacobian to 0.3 for optimized mesh.1.Delete the elements on the displayed in the graphics area.2.Click comps and select the block component form the list.3.For the minimum jacobian, enter 0.3.4.Click mesh to generate the mesh.Go to HyperMesh Tutorials