A medium-temperature waste-heat recovery system based on the organic Rankine cycle (ORC) is designed to recover the exhaust energy from a heavy-duty diesel engine. Analysis of the 1st law of thermodynamics for an ORC ...A medium-temperature waste-heat recovery system based on the organic Rankine cycle (ORC) is designed to recover the exhaust energy from a heavy-duty diesel engine. Analysis of the 1st law of thermodynamics for an ORC system is performed. This analysis contains two parts. The first part is an analysis with undefined heat exchangers to gain an understanding of the ORC and find out suitable organic fluid parameters for a better ORC efficiency. The second part of the analysis uses combined engine test results and two designs of heat exchangers. By comparing the two designs, an improved system of heat exchangers is described. This analysis also quantifies the effect of engine parameters on ORC system. The study concludes that the supercritical Rankine cycle is a better approach towards waste heat recovery. The ORC system is found to perform better under part-load conditions if the medium-high power condition rather than rated working point of the engine is used as the design parameter. The ORC system achieves the highest waste-heat recovery efficiency of up to 10-15% for the optimised heat ex-changer design.展开更多
Commercial vehicle industry worldwide is facing challenges from environmental pressures,stringent limits of CO_(2) emission,governmental regulations as well as ever-increased customer demands.This paper analyzes the a...Commercial vehicle industry worldwide is facing challenges from environmental pressures,stringent limits of CO_(2) emission,governmental regulations as well as ever-increased customer demands.This paper analyzes the above-mentioned challenges,especially in China,including the potential improvement to increase the brake thermal efficiency(BTE),with five levels of BTE proposed,ranging from current 45 to 60%in future,corresponding to China fuel consumption regulation(CFCR)in different phases.The authors also proposed the technology roadmaps to meet the upcoming CFCR3 and CFCR4;finally,the authors draw the conclusions to conform with ever-stringent regulation in China.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 51076013)the Specialized Research Fund for the Doc-toral Program of Higher Education of China (Grant No. 20101101110008)
文摘A medium-temperature waste-heat recovery system based on the organic Rankine cycle (ORC) is designed to recover the exhaust energy from a heavy-duty diesel engine. Analysis of the 1st law of thermodynamics for an ORC system is performed. This analysis contains two parts. The first part is an analysis with undefined heat exchangers to gain an understanding of the ORC and find out suitable organic fluid parameters for a better ORC efficiency. The second part of the analysis uses combined engine test results and two designs of heat exchangers. By comparing the two designs, an improved system of heat exchangers is described. This analysis also quantifies the effect of engine parameters on ORC system. The study concludes that the supercritical Rankine cycle is a better approach towards waste heat recovery. The ORC system is found to perform better under part-load conditions if the medium-high power condition rather than rated working point of the engine is used as the design parameter. The ORC system achieves the highest waste-heat recovery efficiency of up to 10-15% for the optimised heat ex-changer design.
文摘Commercial vehicle industry worldwide is facing challenges from environmental pressures,stringent limits of CO_(2) emission,governmental regulations as well as ever-increased customer demands.This paper analyzes the above-mentioned challenges,especially in China,including the potential improvement to increase the brake thermal efficiency(BTE),with five levels of BTE proposed,ranging from current 45 to 60%in future,corresponding to China fuel consumption regulation(CFCR)in different phases.The authors also proposed the technology roadmaps to meet the upcoming CFCR3 and CFCR4;finally,the authors draw the conclusions to conform with ever-stringent regulation in China.
