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arXiv · 1803.04688

Free Form Deformation, mesh morphing and reduced order methods: enablers for efficient aerodynamic shape optimization

F. Salmoiraghi·A. Scardigli·H. Telib·G. Rozza
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Abstract

The work provides an integrated pipeline for the model order reduction of turbulent flows around parametrised geometries in aerodynamics. In particular, Free-Form Deformation is applied for geometry parametrisation, whereas two different reduced-order models based on Proper Orthogonal Decomposition (POD) are employed in order to speed-up the full-order simulations: the first method exploits POD with interpolation, while the second one is based on domain decomposition. For the sampling of the parameter space, we adopt a Greedy strategy coupled with Constrained Centroidal Voronoi Tessellations, in order to guarantee a good compromise between space exploration and exploitation. The proposed framework is tested on an industrially relevant application, i.e. the front-bumper morphing of the DrivAer car model, using the finite-volume method for the full-order resolution of the Reynolds-Averaged Navier-Stokes equations.

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F. Salmoiraghi, A. Scardigli, H. Telib, G. Rozza. 2018-03-13. Free Form Deformation, mesh morphing and reduced order methods: enablers for efficient aerodynamic shape optimization. https://arxiv.org/abs/1803.04688

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