近十年来, 由于能源和环保的要求, 火花点火天然气发动机以高效、低污染燃烧的优点正在迅速发展。为了分析和研究这种发动机的燃烧过程, 预测多种参数变化对性能的影响, 建立了火花点火式天然气发动机的准维燃烧模型。根据倒拖发动机的实验结果, 对缸内紊流的衰减和产生进行了模化, 提出了缸内紊流强度计算的方法。试验表明, 模型的计算值和试验值具有很好的一致性。该模型计算精度高、工程应用方便, 为缸内燃烧过程分析、性能预测提供了一种有效的工具。

介绍了火花点火式变组分煤层气发动机的主要设计过程。通过发动机台架试验，在不同点火提前角、不同甲烷浓度和不同压缩比时对该发动机的起动、怠速稳定性和排放特性进行了分析。结果表明，变组分煤层气发动机起动、怠速稳定，带负荷工作可靠。通过控制合适的空燃比，可以适应甲烷浓度大范围变动的煤层气燃烧。未燃HC和CO排放量随负荷、甲烷浓度增加而降低；;NOx排放量随负荷、甲烷浓度增加而增加。

Alternative fuel engines have widely been developed in the world due to the decrease of oil resources and the strictness of exhaust regulation. This paper introduces the main processes of designing the diesel engine fuelled with coal-bed gas and ignited by spark plug, and analyzes a number of problems considered in processes of designing the engine. As an example, the characteristics of a coal-bed gas engine converted from a S195 diesel engine are introduced, and the performances of the prototype engine are discussed based on the results of engine testing. And some significant conclusions were got.

提出了一种适合于车用涡轮增压柴油机实时仿真的压气机特性计算方法，应用方便，计算时间少。对一台6缸增压柴油机压气机特性的实例计算表明，此方法具有较好的计算精度。

Natural gas engines have widely been developed in the world because of the decrease of oil resources and strictness of the exhaust regulations. This paper introduces the main processes of designing diesel engines fuelled with natural gas and ignited by spark plugs. Secondly, it analyzes a number of problems considered during the process of designing. As an example, authors introduce the characteristic of a natural gas engine converted from a 4125 diesel engine and discuss the performances of the prototype engine according to results of the engine bed testing .The result is satisfying.