基于热力学第二定律的直喷式柴油机性能分析

这项研究的目的是发展用热力学第二定律分析柴油机在不同运行工况性能的能力.研究是针对一台12150L型柴油机进行的,以发动机气缸内部压缩、燃烧、膨胀、瞬时传热和换气过程的理论模拟模型为基础,应用热力学第二定律分析,度量各种能量品质的优劣和不可逆损失值,并且与热力学第一定律的能量平衡进行了比较.分别改变循环喷油量、燃烧开始角、燃烧持续期及燃烧品质指数.研究了参数变化对缸内可用能和热力学第一定律效率和第二定律效率的影响.

Analysis of Direct Injection Diesel Engine Performance Based on the Second Law of Thermodynamics

The puspose of this study is to develop the capability of second law analysis to diesel engine preformance for different operating conditions. The investigation is carried out for a 12150L diesel engine on basis of the theoretical simulation model of in-cylinder compression, combustion, expansion process, instantaneous heat transfer as well as intake and exhaust processes. Energy quality and irre-versibility are quantified by second law availability balance, and are compared with the first law energy balance. The parametric effects on in-cylinder availability, first law and second law efficiencies are calculated by changing fuel amount injected per cycle, combustion start, combustion duration and heat release factor, respectively.