Abstract: Contrast analysis is carried out on the organic working mediums which applied to high temperature solar organic Rankine cycle (ORC) power generation system. The design of organic radial inflow turbine used in ORC power generation system is studied. According to the given heat source parameters and power, detailed aerodynamic design and multi-parameter comparative analysis is carried out by selecting toluene, C12(dodecane), D4(octamethyl cyclotetrasiloxane), MDM(octamethyl trisiloxane), MM(hexamethyl disiloxane). Based on the contrast analysis above, aerodynamic design, 3d modelling design and computational fluid dynamics (CFD) simulation method reaserch on the radial inflow turbine are made by using toluene as working substance. The calculation results show that toluene ORC system has the smallest mass flow rate and the highest system thermal efficiency. By CFD simulation, relative errors of the status parameters are within 2%, power and wheel efficiency is respectively 3.16% and 2.9% larger than aerodynamic design. The consistency of simulation results and aerodynamic design result indicates the accuracy of the thermodynamic design. Simulating the whole machine confirms that the radial inflow turbine used in organic rankine cycle has a good aerodynamic performance.

Key words: aerodynamic design, numerical simulation, organic rankine cycle(ORC), radial inflow turbine