Numerical Analysis to Visualize the Flow Pattern
Inside Air Turbine

Abstract

Distributed power generation making use of efficient technologies such as organic Rankine cycle (ORC) and compressed air energy storage (CAES) are getting growing
attention with ever increasing demand on energy. A key component for such systems is the expander and its performance has a significant effect on the overall system efficiency. The following work focuses on the expander of such a system by proposing an efficient and comprehensive methodology for developing a small-scale radial inflow turbine RIT). The methodology consists of 1-D modelling,3-D aerodynamic investigation and structural analysis, and a comparison between the performance of a single stage expansion and two stage expansion between same pressure limits. The 1-D modelling proved to be very effective in determining the mean line geometry and performance of turbine based on parametric studies of turbine input design variables.But with CFD analysis, it can be seen that more efficient turbine geometry can be attained, that provides more realistic turbine performance by capturing the 3-D fluid flow behaviour and improves the turbine efficiency with the aid of parametric studies of turbine geometry parameters.The CFD model can predict turbine efficiency and power with accuracy of ±16% and ±13% respectively for a wide range of tested operating conditions. Such results highlights the effectiveness of the proposed methodology and the CFD model can be used as benchmarking model for analyses of small-scale RITs.