The role of dense gas dynamics on organic rankine cycle turbine performance

In this paper we investigate the real gas flows which occur within Organic Rankine Cycle (ORC) turbines. A new method for the design of nozzles operating with dense gases is discussed, and applied to the case of a high pressure ratio turbine vane. A Navier-Stokes method which uses equations of states for a variety of working fluids typical of ORC turbines is then applied to the turbine vanes to determine the vane performance. The results suggest that the choice of working fluid has a significant influence on the turbine efficiency