Application of an Aerothermal Model for Effusion Cooling Systems and Finite Rate Chemistry in Aero-Engine Combustors

Abstract

Effusion cooling is an advanced cooling concept for modern aeroengine combustors and offers a very stable convective coolant film along the wall combined with heat removal inside each hole. In order to find the best positions of the cooling holes, CFD calculations with conjugate heat transfer can be done to predict wall temperature distributions. An extensive CFD simulation with local grid refinement is required to evaluate near wall phenomena. A combustor with complex effusion hole pattern leads to large computational meshes for both the fluid and the solid increasing the computational costs. A helpful approach to speed up calculations is to replace the cooling holes by a set of new in-and outflow boundary conditions for virtual effusion holes. Computational costs and time for the design process can be saved. In the paper the cooling concept of a combustor liner with 368 virtual cooling holes is shown and the influence of the combustion near the wall is investigated. The combustion model used allows to account for kinetic effects in the near wall region.