2-D Meshing on Bottle-Cap Model

Aim:

• To clean up the geometry of the given component and to extract the mid surface from it.
• To mesh the component with given element Quality criteria and to assign the thickness for the same.

Procedure:

1. Model file Opening and check for geometry errors.

Import the model file in ANSA and check for the geometry errors, when the file has imported there are many errors like Triple Cons, Needle Face and Crack Between Cons and these errors can be eliminated manually by using Release and Paste under Cons module and Delete, Topo under Face module

Fig 1: Checking the geometry

Fig 2:Done with Geometry Error

2. Mid surface Extraction, Setting PID's and Material

After the geometry clean up now its the time to extract the mid surface from the model and before that we need to check with the thickness of the model at different locations by using the Measure tool.

Fig 3: Storing the measured value

With the help of Focus tools like inot, or, neighb we can easily focus on a specific area and extract the mid surface. For the mid surface extraction, we have offset and middle options from the face module

Offset: Helps to extract the new face at a certain distance from the selected face.

Middle: Helps to extract the new face at the exact middle of the selected two opposite faces.

Fig 4: Extracted the mid surface using the offset and middle options

After the mid surface extraction, we need to give a separate PID's to the extracted mid surfaces along with the materials terms. For the new PID's initialization, we need to select the Set PID option from the Face module. At the time of giving property for the PID, we need to assign the thickness to it

Fig 5: PID's

3. Meshing the component with Quality Criteria

Fig 6: Quality Criteria

Fig 7: Mesh Parameters

For meshing the component we need to Refine the perimeters and macros to the average element length which is provided in the quality criteria. With the help of the best option under the Mesh Generation module we can able to mesh the property individually and the most cases the mesh will be of good flow since it is made with a good algorithm and we get good mesh output if the selected area is rectangle part. So dividing the area into a macro area is a must get a better mesh flow.

In case if it gives a poor mesh due to a complicated area so we can use the Reconstruct and smooth options under the Shell Mesh module and for eliminating the opposite trias and off elements we can use the split, swap, Join options under the Elements module can be used.

MV Free under Grids module which can be used to move a single or group of node separately in any direction to get rid of the 'off elements' in the quality criteria.

Fig 8: Meshed component

Fig 9:Assigned thickness to Mid surface

Learning outcomes:

• Familiarised with the manual mid surface extraction using the middle and offset method.
• MV Free option under Grids module used in order to eliminate the 'off elements'

Conclusion:

The mid surface is extracted properly and meshing is done with proper quality criteria

The link is provided below:

https://drive.google.com/drive/folders/11yDE5ufJFRsBfKV7vQL12vlrxgpBztgH