Efficient Unstructured Hybrid Meshing and its Quality Improvement for Design Optimisation of Turbomachinery

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European Conference on Computational Fluid Dynamics ECCOMAS CFD 2006 P. Wesseling, E. Oñate, J. Périaux (Eds) © TU Delft, Delft The Netherland, 2006

Efficient Unstructured Hybrid Meshing and its Quality

Improvement for Design Optimisation of Turbomachinery

Names

1

_{Daisuke Sasaki, Caleb Dhanasekaran, Bill Dawes}

2

_{Shahrokh Shahpar}

Affiliations

1

_{Department of Engineering, University of Cambridge}

2

_{Aerothermal Methods Group, Rolls-Royce plc.}

Countries United Kingdom

e-mails ds432@cam.ac.uk, pcd@eng.cam.ac.uk,

wnd@eng.cam.ac.uk, Shahrokh.Shahpar@rolls-royce.com Keywords:

Unstructured hybrid meshing, mesh quality, mesh adaptation, design optimisation Objectives :

Develop a rapid robust hybrid (structured-unstructured) meshing tool based on mapping (parametric and Delaunay-graph mapping) for changes/deformation of geometry.

Improve mesh quality and maintain its quality throughout optimisation process. Implement automatic mesh adaptation for geometry and flow.

Validate the robustness and reliability of unstructured hybrid meshing technique.

Applications :

Automatic robust unstructured hybrid meshing is indispensable for the success in design optimisation. In addition, it is important to maintain the mesh quality for deformation of geometry throughout the optimisation process for the reliability of optimal design. Mesh adaptation is useful to capture the flow feature which can highly affect flow properties. Therefore, the present hybrid-meshing technique with adaptation is applied for various turbomachinery components to validate its robustness. In addition, a turbine blade is used to compare the effects of mesh for the optimisation.

Results:

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D. Sasaki, C. Danasekaran, B. Dawes and S. Shahpar

2. Effect of mesh quality for design optimisation with large deformation of turbine blade is investigated by using structured mesh, unstructured hybrid mesh without adaptation, and unstructured hybrid mesh with adaptation (Figure 2).

Future:

The developed tool will be used to generate fast and robust mesh for aerodynamic and acoustic computation in various turbomachinery optimisation problems.

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Figure 1 : Flow around turbine blade; (a) structured mesh; (b) hybrid mesh without adaptation.

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