Turbulent flow analysis in auxiliary cross-flow runner of a Proto X-3 Bioenergy micro gas turbine using RNG K-ε turbulence model

Simple and wide range application of cross-flow runner has lead its application to a Proto X-3 Bioenergy Micro Gas Turbine (MGT) that has been developed. The MGT is a dual-stage radial compressor-turbine type. Furthermore, highly turbulent flow inside the cross-flow fan need accurate analysis. CFD method with RNG k-ε choosen based on models characteristics. This paper analyzed the flow inside the fan based on the experimental data of the MGT and the result represented by several parameters of turbulent flow. The simulation condition were assumed to be isothermal due to the small temperature difference with the tubulent Prandtl number Pr_t = 1. The result shows several specific vortex inside the runnner. Recirculation flow cthat caused the eccentric vortex occurs at the inner side while the throughflow occurs at the outerside of the fan. The mass flow rate conducted by CFD simulation shows a good agreement with the actual mass flow rate of the cross-flow runner. The results that presented by velocity magnitude, absolute pressure, eddy dissipation, and turbulence kinetic energy shows a realistic on each turbulent parameter based on they trends. This results shows that the method used is prospective to be applied both on analysis or design of the cross-flow runner.