内燃机余热利用分流二氧化碳动力循环热匹配研究  

Thermal Matching Analysis of a Splitting CO_(2) Transcritical Power Cycle in Engine Waste Heat Recovery

作　　者：李力耕 田华[1] 舒歌群[1] 石凌峰 张洪飞 王竞宇 LI Li-Geng;TIAN Hua;SHU Ge-Qun;SHI Ling-Feng;ZHANG Hong-Fei;WANG Jing-Yu(State Key Laboratory of Engines,Tianjin University,Tianjin 300072,China;Department of Thermal Science and Energy Engineering,University of Science and Technology of China,Hefei 230027,China)

机构地区：[1]天津大学内燃机燃烧学国家重点实验室,天津300072 [2]中国科学技术大学,合肥230027

出　　处：《工程热物理学报》2021年第7期1667-1675,共9页Journal of Engineering Thermophysics

基　　金：国家自然科学基金重点项目(No.51636005);国家自然科学基金青年项目(No.51906237)。

摘　　要：二氧化碳动力循环在高效利用内燃机多股余热方面具有很大潜力,基于换热器分流的设计能够显著改善内燃机排气的利用情况。但是,当前研究仍缺少完善的热匹配性及参数分析,来综合权衡基于换热器的分流设计思路带来的热力学性能改变。因此,本文以热源理想匹配过程定义等效比定压热容物性作为出发点,阐述分流设计对于温度匹配机制的影响。结果发现了理想比热具有独特的双峰特性,而分流设计能够有效匹配双峰特性,显著改善外部热源利用率和内部热匹配性,继而提高系统净输出功。CO_(2) transcritical power cycle(CTPC)has great potential in the utilization of the exhaust waste heat from internal combustion engines.The heat exchanger-based splitting design is capable of improving the engine exhaust utilization significantly.Nevertheless,the current research is still lack of thermal matching and parameter analysis to comprehensively balance the thermodynamic performance caused by the splitting design.Therefore,this paper demonstrated the influence of the splitting design on thermal matching mechanism based on the definition of equivalent specific heat capacity in the ideal thermal matching process.The results showed that the ideal specific heat has unique bimodal characteristics,and the splitting design could match the bimodal characteristics effectively,which contributed to improve the external heat source utilization and internal thermal matching,and then promote the net power output of the system.

关 键 词：跨临界二氧化碳动力循环 内燃机 分流 热匹配 

分 类 号：TK123[动力工程及工程热物理—工程热物理]