Week 2 Challenge : Surface meshing on a Pressure valve

Aim : Performing geometrical cleanup and meshing on the given model (Pressure Valve) inorder to prepare it for pre-processing stage of CFD,by using suitable Meshing algorithm with Target length of 1mm,3mm,5mm.

Procedure:

To pre-process a model for CFD process, there are few steps involved in it. Firstly, Geometry Cleanup and second is Meshing.

1.Geometry Cleanup

After loading the given model into ANSA software, checked for proper completion of geometry by using TOOLS>>CHECKS MANAGER >>GEOMETRY for geometrical and penetrations errors. Based on the error report cleaned up the model using TOPO tool.

Found few unfinished faces, penetration of one object(Spring) into another(Column), and open coons of single and double coons. Unfinshed faces/double coons were filled by using different tools like creating new face using FACES tool with appropriate usage of tools under it(Planar, Coons, Loop).Also used Fill Hole option in CONS tool.

To clear penetration errors used Intersect option in FACES tool,followed appropriate procedure to cleanup.

Later assigned PID's for each child parts of a parent object.

2.Meshing

After geometry cleanup of the model,it is taken for Meshing process.Here used CFD algorithm with Visible option In MESH GENERATION tool with target length of 5mm at first.

Used tria elements in mesh generation.But found that the tria elements in the mesh are growing from coons to the centre of the macro.The obtained result is considered as not a good and proper mesh. As the main motive is to generate a good quality mesh,used another Mesh Algorithm called AUTOCFD from Spacing option in Perimeters Tool with tria element length as 5mm.

The given length of tria element is of 5mm with max/min length is of 5.5 and 4.5mm respectively. But the spring element in the model is with minmum distance between the two nodes measured as ~2.5mm which is lesser than the min. length. As a result found that whole spring geometry is not covered with this length.

It is important to cover the whole geometry into consideration, i tried by further reducing the tria element length to 3mm with max/min length is of 3.5 and 2.5mm respectively for the whole body.

Found that the whole geometry is not covered in meshing,resulting in undesireable mesh. i tried by further reducing the tria element length to 1mm with max/min length is of 1 and 0.5mm respectively for the whole body.

With this, the whole geometry is covered in the mesh.

RESULT:

CONCLUSION:

The obtained mesh with tria element length of 1mm is found as satisfactory,finalising it as good quality mesh.

LEARNING OUTCOMES:

Importance of Topology cleanup

Selection of appropriate tool for faces cleanup/geometry cleanup.

Conforming the whole geometry coverup while meshing.

Choosing appropriate algorithm for Meshing.