Comparison Of Turbulence Methodsrnin Cfd Analysis Of Compressiblernflows In Radial Turbomachines

摘要

Purpose - The purpose of this paper is to show the superior turbulence method in CFD analysis of radial turbo machines and to introduce the best way tornchoose turbulence parameters whenever FLUENT user applies this software as a complementary design tool for high-speed turbo machinery components.rnDesign/methodology/approach - One of the most important issues in CFD is analysis of flow field in turbo machines. Flow in high-speed radialrnturbo machinery is a 3D, turbulent and unsteady behavior so needs suitable method for converging. It is clear that the turbulence model has anrnextraordinary effect on investigation of 3D flows in high-speed turbo machinery. A centrifugal compressor of micro and radial turbines have beenrndesigned and simulated 3D using the commercial CFD-code FLUENT 6. Three turbulence models k-ε/standard, renormalization-group (RNG) and RSMrnwere considered and results of three models were compared with experimental and 1D design results.rnFindings - The study showed numerical results are compatible with experimental performance data. It determined that RNG method in CFD analysis ofrnradial turbo machines has provided better results than the standard k-s method. In addition, when using the RNG method, the phenomena of flow fieldrnwere more visible than other methods.rnOriginality/value - This paper offers use of the RNG method as a superior turbulence method in CFD analysis of radial turbo machines.