How to Refine 2-D Meshes

When using the Superdraw sketching and meshing tools to build a two-dimensional (2-D) model directly within FEMPRO, you can refine the initial 2-D mesh by using refinement points. For example, if you want the mesh to be finer at the location of peak results or around features such as a fillet or a hole, you can simply add refinement points to automatically create a finer mesh in the desired regions and a coarser mesh for the rest of the model. The refined mesh will allow for a more accurate and efficient solution.

The process of refining a 2-D mesh is illustrated by the following example. After creating sketches of the wireframe for each part and specifying meshing options, generate the 2-D mesh. (For a summary of Superdraw 2-D sketching and meshing tools, see How to Sketch and Mesh 2-D Models.) Determine what regions of the mesh need refinement. In the model shown in Figure 1, we wanted the mesh to be finer in the regions of the weldments (yellow and cyan).

Figure 1: In the initial mesh, it was determined that refinement was needed in the weldment (yellow and cyan) regions.

To refine an existing mesh, right click on the "2-D Mesh" heading in the tree view for one of the parts of the mesh and choose the "Modify" command. The "2-D Mesh Generation" dialog will appear and the sketches will be displayed.

Add a refinement point to a sketch by right clicking at the location where you want to define the refinement point and choosing the "Add Refinement Point..." command (see Figure 2).

Figure 2: Specifying the location for a refinement point.

The "2-D Mesh Refinement" dialog will appear. Specify parameters for the refinement point including choosing between three types of refinement: divide, radius divide and mesh size. For this model, the "Divide Factor" field was set to 3 to specify that the line segments in the refinement region will be divided into three segments (see Figure 3).

Figure 3: Specifying parameters for the refinement point.

After adding refinement points to the weldment regions, click on the "Preview" button in the "2-D Mesh Generation" dialog to display a preview of the refined mesh (see Figure 4).

Figure 4: The mesh surrounding the weldment regions was significantly finer after adding refinement points and recreating the mesh.

After meshing, the "Preview" button will change to "Sketch", which you can use to return to the sketch and further refine the mesh if desired. When you are satisfied with the mesh, click on the "OK" button to accept the mesh.

With the mesh satisfactorily refined, you can specify the needed analysis data including element definition, loads, constraints and analysis parameters and then analyze the model.

Thus, the ability to refine a 2-D mesh provides increased accuracy and efficiency for 2-D modeling and analysis. For a step-by-step demonstration of 2-D sketching and meshing capabilities including mesh refinement, see the Modeling with 2-D Elements Tutorial.

For more detailed information, see the ALGOR User's Guide.