thermodynamic and environmental analysis of a dual-pressure organic rankine cycle for waste heat recovery from a turbocharged diesel engine fueled with ethanol and methanol blends

This paper refers to retrieving the lost heat of exhaust gas and working fluid of a turbocharged diesel engine employing a dual-pressure organic rankine cycle. the efficiency and emission of diesel compression ignition engines are studied by considering a one-dimensional twozone thermodynamic model. in the proposed system, exhaust gas and intercooler waste heat have been utilized in the high and low-pressure evaporators, respectively. the used cycle has the capability of reducing the irreversibility of the heat transfer process in the evaporators and increasing the turbines’ power. furthermore, hybrid fuels are used in the turbocharged diesel engine to decrease the level of environmental pollutants. accordingly, an exergy-based thermodynamic approach is employed to analyze a diesel engine’s performance and its emissions. the proposed engine includes diesel fuel mixed with methanol and ethanol with different volume fractions of 5% and 10%. the results indicate a reduction in power and maximum brake torque of the engine as well as a remarkable decrement in the emission of pollutants such as nitrogen oxides and carbon monoxide (equal to 15%) by using the alcoholic compounds with diesel fuel. also, r123 is an appropriate coolant utilized in the dual-pressure organic rankine cycle for recovering the lost heat of the diesel engine.