Week 5 Challenge : Surface wrap on Automotive Assembly

Aim:

The aim of this project is to surface wrap an automotive powertrain. To Merge all 3 models and perform surface wrap using ANSA software.

Engine, Gearbox, Transmission

STEPS: 

1. Import the CAD model
2. Display setup
3. Geometry check-up
4. Creating the PIDs
5. Defining the Element size or length
6. selection of meshing type

Objective:

The objectives of this project are

• To check for the geometrical errors and delete surfaces that are unwanted for the surface wrap.

• To Merge all 3 models and perform surface wrap after clearing geometry.

• The target length for Wrap should be set to 3 mm. 

STEPS TO OPEN A FILE IN ANSA

• Click on File
• Select Open
• Select File (FORMAT .igs/SLDPRT .ansa etc.)
• Click Open
• A translator window appears CLICK OK

a.  Engine Geometry

b. Transmission Geometry

c.  Gear Geometry

                      

As the part gets opened in ANSA, firstly it is in wire mode and in entity mode, for desirable visualization we have to change it to shadow mode (It is the visualisation of the part in solid 3D) and the ENT Mode to PID Mode.

a.  Engine Geometry

b. Transmission Geometry

c.  Gear Geometry

As we change it to PID Mode we need to change the colour of the edges in model for desirable visualization as for this we need to follow the following steps:

a.  Engine Geometry

b. Transmission Geometry

c.  Gear Geometry

1. Steps To Change The Colour Of The Edges In The Model

• Go to Quality criteria option (F11)
• Select the tab Presentation Parameter
• Under visualisation option select Draw CONS in PID
• Click Apply then click on ok.(Now the edges will be in yellow colour ).

a.  Engine Geometry

b. Transmission Geometry

c.  Gear Geometry

1. Checking The Geometry of the Model

• Goto checks option
• Select Geometry
• An information box will appear
• Click on execute to see the error though it should show no geometrical error for perfect meshing .

a.  Engine Geometry

b. Transmission Geometry

• After Cleanup the surface of geometry by deleting unwanted parts and faces present on the geometry. As surface wrapping is generally carried out to study the flow over a surface So the main importance should be outside surface rather inside parts and surface. 
• Close all the holes present in the geometry otherwise while wrapping it might create disturbances. Below diagram shows final geometry before assembly.
•  Repeat step 1 and 2 for all the geometries.

a.  Engine Geometry

b. Transmission Geometry

 

c.  Gear Geometry

    4.  From file section select Merge and select other geometric file and click ok. Thus it create an assembly of different parts. The below figure shows the merged assembly.

Remove the triple cons and discontinuous surfaces like rings and extra features which do not play the part in the single volume we need to achieve.

After performing topo-clean, we need to merge the 3 parts together and form a single volume so that surface mesh can be achieved perfectly.

Merge can be done by selecting the merge option under file and select the gearbox, transmission files and perform the merge.

After performing merge we can now perform surface mesh. But first, we need to delete the excess PID create and can be done by compress and only the required PIDs can be kept.

• Go to mesh,
• Choose wrap under mesh generation.
• Click and hold on wrap and a drop-down appears.
• Choose constant length.

Create a new wrap octree and upon double-clicking it a pop-up window appears, where we are required to give mesh parameters.

  

Click on the Parameters section, enter the mesh length as 3.

• Click on contents and select all the PIDs to be meshed and surface wrapped.
• Click on RUN to perform wrap on the selected PIDs.
• The surface wrap is achieved.

Results:

Wrapped mesh:

Completed surface wrap ANSA file: https://drive.google.com/file/d/1M59uJwsLaKPYIzG9QEgJYl_QPFspbFry/view?usp=sharing

Conclusions:

The surface wrap is achieved on the given powertrain components with a total of 703018 elements. The surface is easier to perform since it does not depend on the quality of the wrap on each material as we are not interested in physics in the body. The effective surface wrap is achieved on the given body for a given mesh length of 3mm.