基于双有机朗肯循环的柴油机余热回收系统性能分析

为了有效回收柴油机的尾气、冷却介质和进气中冷的能量,针对一台六缸柴油机,设计了一套双有机朗肯循环系统,结合Aspen plus软件对该系统进行建模,研究双有机朗肯循环系统的运行性能,分析柴油机燃油经济性.经研究发现,加装双有机朗肯循环系统可有效改善原柴油机的热力学性能和经济性能.在设定的柴油机工况下(转速2 000 r/min、转矩1 313 N·m),双有机朗肯循环系统的总净输出功率最高可达43.65 k W,柴油机-双有机朗肯循环联合系统的有效燃油消耗率和热效率分别可达191.24 g/(k W·h)和37.57%,相比于原柴油机可分别改善13.69%和15.86%.

Performance Analysis of Waste Heat Recovery With a Dual Loop Organic Rankine Cycle System for Diesel Engine

To take full advantage of the waste heat from a diesel engine, a set of dual loop organic Rankine cycle ( ORC ) system was designed to recover exhaust energy, waste heat from the coolant system, and released heat from turbocharged air in the intercooler of a six-cylinder diesel engine. Aspen plus software was used to model the dual loop ORC system. According to the simulation model, the operating performance of the dual loop ORC system and the fuel economy of the diesel engine wereinvestigated. The results show that the thermodynamic performance and economy performance of the diesel engine can be effectively improved by using the dual loop ORC system. Under the certain engine operating conditions, namely, engine speedis 2 000 r/min and engine torqueis 1 313 N·m, the total net power output of the dual loop ORC system is up to 43. 65 kW. The brake specific fuel consumption ( BSFC ) and the thermal efficiency of the diesel engine-dual loop ORC combined system are 191. 24 g/( kW·h) and 37. 57%, respectively. Compared with the diesel engine, the thermal efficiency of the combined system can be increased by 13. 69% and the BSFC can be reduced by 15. 86%.