Document Type : Original Article
Department of Mechanical Engineering, Babol Noshirvani University of Technology, Babol, Iran
Department of Mechanical Engineering, Payame Noor University, Tehran, Iran
In this paper, the normal exergy scrutiny (NES) and advanced exergy scrutiny (AES) of a waste heat recovery (WHR) system was performed. The proposed system contains a dual-loop organic Rankine cycle (DORC) which recovers the available waste heat of the intake air, exhaust gas, and coolant streams of a 12-cylinder heavy-duty stationary diesel engine. A well-known method of the AES called the thermodynamic cycle approach is utilized to determine each component exergy destruction parts namely exogenous/endogenous, unavoidable/avoidable, etc. Results showed that 59.04 kW from the 258.69 kW total exergy destruction rate of the system could be eliminated (22.82% of the total exergy destruction rate). The total avoidable exergy destruction part of the low-temperature loop accounts for 46.62 kW, which indicates that it requires more attention than that of the high-temperature loop by 12.42 kW. Furthermore, it is revealed that to enhance the overall productivity of the system, there is a relatively significant difference in priority order regarding the improvement of system components. The AES has proposed this ranking for improvement priority of components: condenser, expander 2, expander 1, respectively. While the NES has specified the priority as the evaporator 1, condenser, expander 2, respectively.