Internal combustion engines (ICEs) are the major consumers of crude oil, and thus improvements in the fuel consumption performance of ICEs would be significant for global energy conservation and emission reduction. Owing to the constraints in the engine structure and combustion efficiency, more than half of the fuel combustion heat in ICEs is wasted. Therefore, ICE waste heat recovery (ICE-WHR) shows huge potential. Rankine cycle (organic or inorganic) provides a promising solution for ICE-WHR, which could balance efficiency and practicality. In this review, recent advances in Rankine cycles for ICE-WHR are summarized and discussed. To evaluate results from various existing studies, a uniform evaluation standard, thermodynamic perfection, was proposed based on the benchmark of the heat source based ideal thermodynamic cycle(H-iCycle), which is determined by achieving ideal thermal matching to external boundary conditions. Based on this, the effects of three major factors (cycle configuration, working fluid, and key components) on the performance of Rankine cycle can be investigated. In addition, a discussion of several application concerns, including backpressure, weight, power output type, off-design performance dynamic response, and control, enables us to gain a comprehensive understanding and assessment of Rankine cycles in ICE-WHR. With respect to working fluids, C_xH_yO_z and siloxanes with high critical temperature (such as cyclohexane, benzene, toluene, and MM) have a satisfactory thermal matching with waste heat sources. Basic Rankine cycles using these working fluids could yield a high thermodynamic perfection of up to 54.1%. With respect to the cycle configuration, cascade Rankine cycles and dual-pressure Rankine cycles are expected to achieve the highest thermodynamic perfection of 62.3%. Finally, major challenges and perspectives for the future development of Rankine cycles in ICE-WHR are discussed. Four promising research directions suggested in this review include the active design of desirable working fluids, advanced cycle configuration design based on “energy utilization according to quality,” integrated scheme research at three levels (component, system, and energy management), and advanced coordinative control.

内燃机（ICE）是原油的主要消费者，因此，ICE的燃油消耗性能的改善对于全球节能和减排将具有重要意义。由于发动机结构和燃烧效率的限制，内燃机中的燃料燃烧热量浪费了一半以上。因此，ICE余热回收（ICE-WHR）具有巨大的潜力。朗肯循环（有机或无机）为ICE-WHR提供了有希望的解决方案，可以平衡效率和实用性。在这篇综述中，对ICE-WHR的朗肯循环的最新进展进行了总结和讨论。为了评估各种现有研究的结果，基于基于热源的理想热力学循环（H-iCycle）的基准，提出了统一的评估标准，即热力学完善性，这是通过实现与外部边界条件的理想热匹配来确定的。在此基础上，可以研究三个主要因素（循环构型，工作液和关键组分）对兰金循环性能的影响。此外，对一些应用问题的讨论，包括背压，重量，功率输出类型，非设计性能动态响应和控制，使我们能够全面了解和评估ICE-WHR中的兰金循环。关于工作液，C 包括背压，重量，功率输出类型，偏离设计的性能动态响应和控制，使我们能够全面了解和评估ICE-WHR中的兰金循环。关于工作液，C 包括背压，重量，功率输出类型，偏离设计的性能动态响应和控制，使我们能够全面了解和评估ICE-WHR中的兰金循环。关于工作液，C_X ħ _ÿ ö _ž临界温度高的硅氧烷（例如环己烷，苯，甲苯和MM）与废热源的热匹配令人满意。使用这些工作流体的基本兰金循环可以产生高达54.1％的高热力学完美度。就循环构型而言，级联兰金循环和双压力兰金循环有望实现62.3％的最高热力学完美度。最后，讨论了ICE-WHR朗肯循环未来发展的主要挑战和前景。这篇综述提出了四个有希望的研究方向，包括积极设计所需的工作流体，基于“按质量利用能源”的先进循环配置设计，三个层次（组件，系统和能源管理）的集成方案研究，