Experimental study on a Tesla turbine integrated into a Mini-ORC system using R245fa as working fluid

The Tesla turbine shows significant potential as an expander for small-scale Organic Rankine Cycle (ORC) systems in waste heat recovery applications. However, experimental studies on Tesla turbines in ORC systems are limited, and the influence of key parameters on turbine and system performance remains underexplored. In this study, a test bench using a Tesla turbine as the expander with R245fa as working fluid was built. By adjusting the pump speed and load current within the system, the performances of the Tesla turbine and ORC system were investigated. The results indicated that when the turbine speed and expansion ratio were increased, the power output initially exhibited an upward trend followed by a subsequent decline. This was a trend different from that of previous studies. Under heat source temperatures of 90–120 °C, the Tesla turbine achieved a maximum power output of approximately 29.5 W at speeds below 14,300 RPM. The maximum isentropic efficiency of approximately 62.28 % was observed at 9335 RPM, which, to our knowledge, represents the highest isentropic efficiency for Tesla turbine in the reported experimental research. • Experimental study of Tesla turbine in the ORC system with R245fa was carried out. • Isentropic efficiency of Tesla turbines reached 62.28 % in the experiment. • Distinct speed-power, pressures ratio -power relations are achieved.