[tel-00339810] SIMULATION NUMERIQUE ET MODELISATION DE L'ECOULEMENT AUTOUR DES PAROIS MULTI-PERFOREES

Effusion cooling is commonly used to cool the combustion chamber liners in aeronautical gas tur bines. The principle is to drill in the liners thousands of perforations through which cooling air is injected inside the combustion chamber. In 3-D combustion chambers computations, the resolution of the flow near the perforated walls is too expensive in terms of computational cost. The objective of this work is to propose a practical model to account for effusion cooling in industrial computations of the fiow inside and outside the combustion chamber. Large Eddy Simulations have been performed in order to get a deeper understanding of the flow around a multi-perforated plate. The configuration of interest is an infinite perforated plate, the computational domain being reduced to a box containing only one per foration and including both sides of the plate. A specific strategy to generate and maintain the flow in such a configuration has been developed for isothermal cases first, and then extended to non-isothermal cases. The data from these Large Eddy Simulations have been analyzed in order to focus the modeling effort on the most important phenomena for effusion cooling. This work has allowed the development of an adiabatic model now commonly used for combustion chambers computations at CERFACS, in the CFD-Combustion team.



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