GEOMETRY CLEAN UP AND VOLUMETRIC MESHING OF A TURBOCHARGER FOR FLOW SIMULATION

OBJECTIVE

The main objective of this project is to do geometry clean up and mesh the turbocharger using the preprocessing software ANSA.

PROCEDURE

• GEOMETRY CLEANUP.
• PID ASSIGNING .
• SURFACE MESHING.
• VOLUMETRIC MESHING.

GEOMETRY CLEANUP

In the wireframe view of the model geometry errors such as single cons and triple cons can be seen clearly.

some of the errors in this turbocharger model are shown in below figures.

Using various tools under the Topo module such as intersect, cut, coons, fitted and much more, the geomerty errors are removed and a cleaned model which is void of any error is obtained. Mainly in all the areas single cons must be removed.

PID ASSIGNING

once the cleaned up model is obtained, then PID\'s are assigned to the various parts of the turbochrager.

SURFACE MESHING

In this model different element lengths are given for each PID and hence, first element length of each PID is defined and then it is meshed using FREE MESH option.

ELEMENT LENGTH OF ALL PARTS OF THE TURBOCHARGER.

• BLADE SECTION 1 1 mm.
• BLADE SECTION 2 2 mm.
• COMPRESSOR CASING 5 mm.
• IMPELLAR 2 mm.
• INLET CASING COVER 5 mm.
• SHAFT ROTOR 1 mm.
• TURBO CASING 5 mm.

Before meshing the model, it is ensured that there are no intersecting surfaces and the blade sections 1,2 and impellar with rotor shaft share a single volume. Then free mesh is done for the whole model and the surface mesh is obtained.

VOLUMETRIC MESHING

As the surfacec mesh is finished, then volumetric mesh is to be done. The first step in the volumetric mesh is to generate the volumes available in the model and selecting the volumes which are required for the analysing part alone. Here there are 8 volumes generated by the software but we need only 4 of those volumes for the CFD flow analysis. Hence the volumetric mesh for those four volumes is alone acrried and the output is given.

CONCLUSION

• GEOMETRY CLEAN UP FOR THE TURBOCHARGER IS DONE.
• ELEMENT LENGTH FOR ALL PID\'S ARE DEFINED
• SURFACE MESH IS CARRIED OUT AND CHECKED FOR ANY ERRORS IN THE MESH.
• VOLUMES NEEDED DURING FLOW ANALYSING ARE CHOSEN AND FOR THOSE VOLUMES ALONE VOLUMETRIC MESH IS CARRIEDD OUT.

LINK FOR THE TURBOCHARGER MODEL - https://drive.google.com/open?id=15ZugV68j86ltr4mNHW2QjN1p8QaGH6bi