Numerical study of three-stream nozzle exhaust flow from a simplified model of a turbofan nacelle

While Computational Fluid Dynamics (CFD) has become a common tool in the design and analysis of a wide variety of fluid flow problems, the accuracy of CFD simulations remains dependent on many physical and numerical variables, namely the physical model of fluid flow (the governing equations and turbulence model), the numerical algorithm and its order of accuracy, the quality and density of mesh etc. Variations in these parameters may lead to inaccurate and sometime non-physical results that are not immediately obvious, limiting the usefulness of CFD in design and analysis. In order to understand the effect of physical and numerical variables on the solution, a number of benchmark problems have been proposed by the aerospace industry, under the auspices of AIAA, both in the areas of external aerodynamics and propulsion. The aim of this study is to conduct CFD simulations of a benchmark problem in aerospace propulsion - the simulation of three-stream nozzle exhaust flow, identified by the AIAA Propulsion Aerodynamics Workshop II. The goal is to identify the best physical and numerical models for accurate simulations of this flow determined by comparisons of CFD results against the experimental data. It is hoped that such benchmark simulations for canonical flows can result in the establishing the best practice guidelines for CFD users.