Document Type : Research Article
Faculty of Mechanical Engineering, University of Tabriz, Tabriz, Iran
Mechanical Engineering Department, Engineering Faculty of Khoy, Urmia University of Technology, Urmia, Iran
This paper refers to retrieve the lost heat of exhaust gas and working fluid of a turbocharged Diesel engine employing a Dual-Pressure Organic Rankine Cycle (DPORC). The efficiency and emission of Diesel compression ignition engine is studied by considering a one-dimensional two-zone 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 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 emission of pollutants such as NOx and CO (equal to 15%) by using the alcoholic compounds with Diesel fuel. Also, R123 is an appropriate coolant utilized in the DPORC for recovering the lost heat of the Diesel engine.