3D Fluid–Solid Heat Transfer Coupling of an Aero Engine Pre-Swirl System

Abstract

This paper examines the application of a newly developed code, which couples a commercial computational fluid dynamics (CFD) code (FLUENT) directly to an in-house finite element solver used by Rolls-Royce plc. The coupling is achieved by passing metal temperatures from the finite element solver to define CFD boundary conditions, and then passing heat fluxes from the resulting CFD solutions back to the finite element model. This coupling method was applied to a real engine test case, modelling the pre-swirl system of the Rolls-Royce Trent 500 aero engine. The initial phase of the analysis couples an axisymmetric finite element whole engine model to two axisymmetric CFD models. The CFD models define the pre-swirl fluid domain during idle and maximum take off engine running conditions. This demonstrates the code’s ability to accommodate temperature transients through the use of multiple CFD models. A further analysis is then performed coupling the same finite element engine model to a 3D CFD model replicating stabilised maximum take off conditions. This is compared with the axisymmetric to axisymmetric analysis to identify the approximations inherent in using an axisymmetric model to investigate a three dimensional flow structure.