Mesh generation of a simple cylinder using ANSA

Objective:

      The goal is to create a mesh that accurately captures the input domain geometry(a cylidrical shape) with high-quality (triangulated) cells so as to make subsequent calculations intractable.

      The above said goal is acheived by using a most widely used Pre - processing software named ANSA.

What is ANSA?

      ANSA is an advanced multidisciplinary CAE pre-processing tool that provides all the necessary functionality for full-model build up, from CAD data to ready-to-run solver input file, in a single integrated environment.

      ANSA is the user\'s preference due to its wide range of features and tools that meet their needs. The list of productive and versatile features is long and the alternative tasks and processes to be completed using them are countless.

Mesh generation:

        Mesh generation is the practice of creating a mesh, a subdivision of a continuous geometric space into discrete geometric and topological cells. Often these cells form a simplicial complex. Usually the cells partition the geometric input domain. Mesh cells are used as discrete local approximations of the larger domain.

Purpose of meshing:

        Meshes are used for rendering to a computer screen and for physical simulation such as finite element analysis or Computational fluid dynamics.

        Finite element calculations cannot be done directly on solid parts. We know to perform those calculations only on points created by the mesh generation process. Thus generating mesh is a must and most important step for any CFD or FEA calculations to be performed.

Steps involved in mesh generation by ANSA:

1. The solid part made using any cad modelling software is imported into ANSA. The Procedure is File>Open and select the required solid part.
2. The solid part is initially imported as a wireframe model in ANSA and it is changed into a solid model by clicking on surface icon as shown below.
3. The geometry is checked using the checks button and selecting the geometry checks option as shown

4. Next step is to assign property id to the solid part. It is very similar to that of assigning boundaries. In order to assign property to the solid part first we have to change from entity mode to the PID mode.

5. After Changing into PID mode go to utilities>quality>presentation parameters and click on view cons as in entity mode button to view the cons  and also by clicking on cross hatches icon the cross hatches are visible.

6. To assign property id to the part click on set pid option under the faces menu in the TOPO module window and select by faces option in the next window.

7. Select each regions and click the middle mouse button and create a new property.The selected regions can be assigned to a particular property ID by double clicking on it.

8. The geometry after assigning the property ID looks as like below.  Now, to generate the mesh, change from TOPO mode to MESH mode. In Mesh Generation select Spot Mesh and define the element type as tria

9. After this in Mesh module, under Perimeter, in length option, the size of the mesh is given after selecting the edges. In this case, the length is 1 unit. 

10. Now,under Mesh generation, spot mesh is selected(1st order). And the whole part is selected and the mesh is generated as shown below.

11. The length between the adjacent nodes can be determined by using Measure function as shown below

12) After meshing the geometry, the surface mesh check is selected under Checks Manager to see whether all the condition of irregularities are passed by checking the status of each condition as green tick mark as shown below.

Thus the mesh generation process is succesfully completed by following the above steps.

Provided below is the google drive link for the ANSA part file.

https://drive.google.com/open?id=1071mkwRRF82jmPZtrOQhJccvNjdRUsRw