Midsurfacing and Meshing of hood model using ANSA 

Midsurfacing and Meshing of hood model using ANSA

Aim : Meshing of Hood using ANSA pre-processor.

Objectives :

For the given component (Hood), checking for the geometrical errors and meshing with the given element Quality criteria. After meshing the component the thickness has to be assigned.

1) To clean up the topological errors.

2) To clean the geometry using different set of tools.

3) Create mid-surface depending on the type of geometry.

4) Assigning perimeter length and meshing the whole geometry.

5) Check the quality parameters

6) Draw shell as solid and check again for any quality issues such as trias

Procedure:

1. The given geometry is checked for any errors for any single cons, triple cons, unchecked faces, Collapsed cons, Needle faces, Overlap faces, Cracks and penetration errors. All the above should be removed inorder to get a good meshing.

2. Mid surfacing is done either by using offset or auto mid surface and properties are assigned to each as shown below. Rm.dbl symmetry is used to check symmetry of the hood model and only half of model is used for meshing purpose. Later on transform will be used to get the total model.

3. Property is assigned to each of midsurface as shown below

4. Before meshing mesh and quality parameters are assigned as shown below

5. Entire model is meshed by focussing on the quality parameter

inner hood

outer hood

full model

the above model is obtained with following quality

6. Draw shell as solid is turned on to reflect the thickness in the meshed mid surface

How required quality is obtained?

the above type of trias are eliminated by using split tool and by using smooth. The output is obtained as below. Trias in same direction are required and all trias at the edge of the perimeter should be avoided.

Conclusion:

The quality criteria was satisfied with 96.24% quad elements and 3.76% of tria elements for the meshing of hood model . A tri element will always be in a plane because it takes a minimum of 3 nodes to specify a plane. A quad element can wrap around required geometry. Therefore, Quads are preferred over trias.