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arXiv · 0801.2047

Numerical studies towards practical large-eddy simulation

Jérôme Boudet·Joëlle Caro·L. Shao·Emmanuel Lévêque
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Abstract

Large-eddy simulation developments and validations are presented for an improved simulation of turbulent internal flows. Numerical methods are proposed according to two competing criteria: numerical qualities (precision and spectral characteristics), and adaptability to complex configurations. First, methods are tested on academic test-cases, in order to abridge with fundamental studies. Consistent results are obtained using adaptable finite volume method, with higher order advection fluxes, implicit grid filtering and "low-cost" shear-improved Smagorinsky model. This analysis particularly focuses on mean flow, fluctuations, two-point correlations and spectra. Moreover, it is shown that exponential averaging is a promising tool for LES implementation in complex geometry with deterministic unsteadiness. Finally, adaptability of the method is demonstrated by application to a configuration representative of blade-tip clearance flow in a turbomachine.

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Jérôme Boudet, Joëlle Caro, L. Shao, Emmanuel Lévêque. 2008-01-14. Numerical studies towards practical large-eddy simulation. https://doi.org/10.1007/s11630-007-0328-3

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