Meshing of Car Hood model

1. Objective:

For the given Hood model, Taking the mid surface for all the components after checking the geometrical errors and meshing the mid surface with the following element Quality criteria.

2. Procedure:

Step 1: Open ANSA Software and Import the CAD model

Step 2: Checking model for Geometrical Error.

Using AutoFix for Fixing Geometrical Error. further, we need to fix the errors manually if auto-fix does not solve our problem. 

Step 3: Setting Orientation

Step 4: Checking PID for the understanding of different parts in the hood.

There are five parts is shown in the model as follows.

Step:5 Assigning the name of different PIDs using the Store Lock Function.

Step 6: Mid Surface Generation

Now before mid-surface generation, we need to view the thickness of the part. while measuring thickness we can see that the thickness of the part is 1.2 mm. so that for confirmation Checking the thickness at various locations and it is found that the overall average thickness is 1.2 mm.

Now for Extracting Mid Surface, we need to use the Offset command where we need to define the face offset value. 

Note: Here the direction of mid surface offset is showing in the opposite direction so that we need to use -0.6 as an input to reverse the offset direction in the middle.

Now, Again we need to check the Geometrical Error. we found that there are some triple cons present in the extracted surface which is needed to fix using the manual method.

To fix the Tripple cons Error we need to use the Release cons command to release the cons and to delete the hot point we are using the delete Hotpoint command. due to this, we can see that that one extra con is present in the part which leads to generating the Tripple cons. using face delete command delete the created cons. again use insert Hotpoint command and Topo to Stich back the surfaces.

After Stich back surface using Topo command, we need to check the geometrical error. this time our geometrical errors are resolved.

orienting the model using the orientation command. 

Similarly, Extracting Mid Surface of other parts and Checking and Fixing the Geometrical Errors. but here the thickness of the top and mid parts are different and have 0.75 mm. also while checking we found that a uniform thickness throughout the part. Here we used Midsurface Generation Command for Directly extracting the mid surface which is a time saver option for simple geometry.

Step 7: Meshing

We are doing meshing one by one on each part. first, we need to define the quality criteria as given in our objective.

To define the mesh length we need to use the Length command in the mesh module. Also, we need to check the holes have even numbers and faces are parallel to the nearby cons before meshing. 

Checking for even Numbers and making the edge of the hole parallel to the nearby feature for better mesh flow. the after meshing result is shown below.

Further, Using Best Mesh Command to Generate the mesh. we got some errors which are due to our quality criteria is not satisfied. We try to fix this issue using reconstruct command and found that the error is resolved and mesh generation is successful as shown below.

Similarly Generating Mesh for Each part and trying to get minimum trias element as shown below.

Step 8: Result

Now Viewing the complete model using All Command Here we see that the overall meshed, unmeshed result.

Conclusion:

In This Assignment, we did the operations such as follows

i. importing geometry,

ii. Checking for Geometrical errors using the Check Geometry command.

iii . Fixing Geometrical Errors using Manual and Auto-Fix Method.

iv. Checking PID and Assigning saving different views using store lock command.

v. Extracting Mid Surface for each part using offset command and Midsurface command.

vi. Again Fixing geometrical Errors using Manual Method. 

v. Orienting the faces using orient command.

vi. Making Holes Parallel to the nearby cons for better mesh flow before meshing.

vii. Using the Best command in the Mesh to generate the mesh.

viii. Avoiding the mesh error by using Reconstruct mesh command.

ix. Reducing Tria Elements as much as possible using Num+/- command and cut command.