Applied Optimisation of a Twin Screw Expander for Electrical Power Generation in a Waste Heat Recovery System Using an Organic Working Fluid

摘要

This research investigates the applied optimisation of a twin screw expander which forms part of a prototypeControlled Phase Cycle (CPC) application, addressing the energy trilemma of emissions reduction, security ofsupply and cost savings in industrial environments. The optimisation of the expander’s performance affordsan opportunity to improve on the low conversion efficiencies displayed by current ORC waste heat recoverysystems, with projected CPC efficiencies upward of 6%.The system uses R1233zd (E) as the organic working fluid and is designed to generate 80 kW of electricalpower by harnessing a 1 MW thermal low pressure steam supply. A comparison of theoretically andempirically derived elements, including the effects of Built in Volume Ratio (BIVR), fluid gas fraction, massflow rate, pressure and temperature on the expander’s operation enable the validation and quantification ofoptimised expander operation.