Abstract A novel realistic Work Criteria Function (WCF) approach has been used to analyze the ideal air-standard Diesel cycle. The WCF formulation gives rise to a new performance criterion which is termed as efficient power density (EPD). Thermodynamic analysis under maximum efficient power density (MEPD) conditions has been performed and compared with other available performance criteria using variable specific heats of the working fluid. The results obtained from this analysis prove that the engine designed under MEPD conditions is very efficient and the size of the engine is reduced significantly compared to those designed under maximum efficient power (MEP), maximum power density (MPD), and maximum power (MP) criteria. Harmful emissions like NO x {\mathrm{NO}_{\mathrm{x}}} may decrease considerably at higher values of the maximum cycle temperature ratio (ξ). The effect of variable specific heats of operational fluid on the actual cycle’s performance has a significant impact on engine performance and should be incorporated when evaluating practical cycle engines. The results obtained in the current study have scientific importance and could be an essential guide for the design of real Diesel engines by engine manufacturers.

中文翻译：

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变工质比热的高效功率密度条件下柴油循环的性能分析

摘要 一种新颖的现实工作标准函数 (WCF) 方法已被用于分析理想的空气标准柴油循环。WCF 公式产生了一个新的性能标准，称为有效功率密度 (EPD)。已经在最大有效功率密度 (MEPD) 条件下进行了热力学分析，并使用工作流体的可变比热与其他可用的性能标准进行了比较。从该分析中获得的结果证明，在 MEPD 条件下设计的发动机非常高效，与最大有效功率 (MEP)、最大功率密度 (MPD) 和最大功率 (MP) 下设计的发动机相比，发动机的尺寸显着减小。 ） 标准。NO x {\mathrm{NO}_{\mathrm{x}}} 等有害排放物在最高循环温度比 (ξ) 值较高时可能会显着减少。工作流体的可变比热对实际循环性能的影响对发动机性能有重大影响，在评估实际循环发动机时应考虑在内。当前研究中获得的结果具有科学重要性，可以成为发动机制造商设计真正柴油发动机的重要指南。