As the mostcommonly used turbine in the ORC system, the radial inflow turbinesare by far the most investigated class of organic vaporexpansion. Bo et al. Conducted the preliminary design andperformance analysis of a 150 kW-class organic working fluid radialturbine for ORC power generation system. Li et al. Studiedaerodynamic optimization for a radial-inflow organic turbine withhigh expansion ratio. Their results showed that the maximum efficiencyof turbine was 84%. The radial-inflow turbine is capable ofgenerating higher power than the positive-displacement expansionengine. However, the organic vapor flows in radial direction relativeto the shaft in a radial inflow turbine. The specific volume of fluidswould continuously keep increasing along the flow direction. Asthe area of cross section of the expander constantly decreases, theheight of the blade has to be gradually increased and as a result, theturbine cannot operate at high vapor flow rates. Due to thismismatch between its geometrical structure and the flow characteristicsinside the turbine, the radial-inflow turbine has aninherent power limitation. In contrast, centrifugal turbines aremore suitable for the requirements of the ORC systems as its geometricconstruction can match its aerodynamic performance quitewell.