Project 1 - Meshing of Floor Panel

2D - Meshing of Floor Panel

Objective:

 For the given Floor Panel model, Take the mid surface after checking the geometrical errors and mesh the mid surface with the given element Quality criteria.

S.No	Quality Criteria	Value
1	Aspect Ratio	5
2	Skewness	45
3	Warping	15
4	Taper	0.5
5	Min. Length	2 Units
6	Max. Length	8 Units
7	Min angle Quad	45
8	Max angle Quad	135
9	Min angle Tria	20
10	Max angle Tria	120
11	Tria %	10

CAD Model Image

Given CAD model has been imported to ANSA and it has lot of geometrical error issues available in the CAD geometry. RAW CAD model and geometrical error are shown below.

RAW CAD Model

RAW CAD Model with Geometrical Errors

The above CAD model has geometrical errors like Unchecked Faces, Collapsed Cons, Trible Cons, Needle Faces, Overlap Faces, Cracks, and Single Cons.

Misaligned Surface

Collapsed Surface with Too many Hot Points

Too Many Hot Points on CONS

Procedure

So, we have to do a geometry cleanup to remove the above errors and then we proceed to mid surface extraction. First, we have to do Topo for that go to Faces>Topo tool is used for all the edges of each component at once to guarantee that all the surfaces are joined correctly. The next step is to run the geometry check for the parameters as shown in the image below by selecting Checks>Geometry. The faults found are shown in a different image.

By right-clicking the problem and selecting "Fix," the majority of the errors were immediately corrected and few errors are corrected by manually.

Next, select Faces>Orient to alter the orientation of every face. This guarantees that the orientation of each face is the same.

Cleaned CAD Model

No Geometrical Error on CAD Model

The following procedure is to separate each component's mid surfaces into their own property ids. By manually offsetting the surfaces of either face to the middle, mid surfaces are extracted. Utilizing the Measure tool from Utilities>Measure, the thickness of each component is first measured. All the geometry were discovered to be -0.5 mm thick. The thickness is constant throughout the component because they are sheet metal parts. The following step is to select List>Properties>New to create properties. Property has thickness allocated to it, and property has a Material named "MS" generated and assigned to it.

After selecting all the surfaces on a face with the Offset tool (Faces>Offset), the mid surface is then taken out. After checking the direction and offsetting, the offset value is set at half the thickness. By selecting Faces>Set PID and assigning to the appropriate property, the property is now allocated to the extracted mid surface. For all the components, all mid surfaces are retrieved and given properties.

Faces Offset

Once more, geometric defects are found in the extracted mid surfaces and corrected. Below is a display of the final extracted mid surfaces.

Extracted Mid Surface

Geometry Check on Mid Surface

Then, select Utilities>Mesh Parameters to configure the mesh parameters. Target length, minimum element length, and maximum element length are set to 5, 2, and 8 in that case. For mixed and first order elements, all other parameters are left at their default values.

The next step is to configure the quality criteria by heading to Utilities>Quality Criteria. The quality criterion file is also stored for later use. The graphic below displays the parameters for the newly defined quality criteria.

Quality Criteria

The mid surfaces must now be ready for meshing. Change to the Mesh module for that. By selecting all the CONS and entering 5 as the target element length value under Perimeters>Length, the shell element length is first changed. The same procedure is followed for all Macros (surfaces).

Perimeter Length Definition

Then, the minimum element length is checked in every region, and any areas where elements would not meet the minimum length are changed.

The Mesh generation>Best tool is then used to mesh. The mesh is created by this tool using the best algorithm available.

Meshes with Quality Issues - 1

Meshes with Quality Issues - 2

Then, using the Shell Mesh>Reconstruct tool, the resulting mesh is polished. There are made sure there be no revolving quads. Trias are also kept to a minimum. The following needs to be ensured when working with trias.

 Meshes with Quality Issues after the Reconstructed Meshes

• No trias touching each other back-to-back or in the other direction
• There are no trias around the edges.
• On a feature, no trias
• low number of trias in a given area

The following tools are utilized to deal with trias:

• Grid>Paste the nodes in order to advance the tria backwards.
• To split an element and advance a triangle, go to Elements>Split.
• To rotate the tria left or right, select Elements>Swap.
• Elements>to create a quad by joining two trias together.

The Shell Mesh>Smooth tool is used to improve the mesh's flow after modification. Any elements that don't meet the required standards are additionally corrected, either by remesh or by smoothing the elements. The produced mesh is displayed below.

The given Floor Panel model's geometry cleanup, mid surface extraction, and 2D meshing were all completed successfully. Additionally, every component meets the quality standards. The model accurately captures every feature with superb mesh flow. Low tria concentration is maintained.

Basic ANSA Software tools and GUI learning outcomes.

• To clear up Floor Panel geometry.
• To assign an attribute and thickness to the mid-surface.
• to mesh the component meeting Quality Criteria with improved mesh flow and reduced trias concentration.

Results