Heat exchangers design and working fluid selection for an organic rankine cycle

Among other technologies the organic Rankine cycle (ORC) can be used to recover waste heat from an internal combustion engine (ICE). This paper describes the performance of exhaust heat recovery using an ORC in a passenger car. The heat transfer properties are evaluated over the engine's entire operating region based on the measured data. Subsequently, a mathematical model of the plate heat exchangers is created based on the specific ORC working conditions. The main aims of this study are 1) the determination of the proper working fluid for ORC system, and 2) the calculation of the heat transfer coefficient and the required surface area for the plate heat exchangers (evaporator and condenser).