以火花点火式S195型煤层气发动机为基础，建立缸内燃烧过程碳化氢(HC)和氧化氮(NO)2种排放物的排放模型，以Matlab程序设计语言为平台，对HC和NO实际排放量进行仿真。计算结果表明，计算值与实测值吻合较好。研究发动机燃用变组分煤层气后HC和NO的排放特性以及煤层气组分变化对发动机HC和NO排放量的影响。提高煤层气中甲烷的体积分数有利于降低HC排放量，但不利于降低NO排放量。

There is a worldwide interest in the research of various alternative fuels for automotive engines for the purpose of reduction of CO2 and toxically harmful exhaust emissions. Coal-bed gas, the main component of which is methane, has been considered an attractive alternative fuel for combustion engines due to its abundant resources, high hydrogen-carbon ratios and very low soot formation tendency. The composition of available coal-bed gas, however, can vary considerably, and this has made its combustion stability difficult to control in conventional spark ignition engines. To overcome the problem, a combustion system with a swirl chamber connected to the main combustion chamber through an orifice has been developed for the use of coal-bed gas in spark ignition engines, and the corresponding combustion process has been studied using a developed combustion model involving flame kernel formation and flame front propagation. The combustion model includes two sub-models with the first dealing with the calculation of turbulence intensity history, and the second modeling a jet flow through the orifice of the swirl chamber. Emissions of NOX, HC and CO have been predicted using the combustion model based on an extended Zeldovich mechanism, wall quenching and incomplete oxidation simulations. The effects of various components in coal-bed gas on the engine combustion process and emissions are also investigated. Validation of the combustion model has been performed through comparing simulation data with the experimental result obtained from a relevant single cylinder research engine, and a satisfactory agreement between them has been achieved in terms of combustion parameters and exhaust emissions.

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。

在电控汽油机参数未作任何调整的情况下，实验研究了汽油机燃用乙醇汽油对发动机经济性和动力性的影响。研究表明：电控汽油机改燃乙醇汽油后，部分负荷时汽油机的功率和转矩有所降低，但全负荷时汽油机的动力输出不变；与普通汽油相比，乙醇汽油的燃油消耗率增加5%-10%，而且汽油机的经济区范围变窄；但能耗率会有所改善，在怠速工况下，乙醇汽油会降低汽油机的CO、HC和NO2排放；乙醇汽油对汽油机性能的影响与空燃比控制策略有关。

介绍了在S195柴油机上进行富氧燃烧的试验，对柴油机排放特性进行了比较与分析，目的是通过试验研究，找到在富氧条件下同时降低碳烟和NOx排放的方法。研究结果表明，增加进气氧的质量分数，碳烟排放大幅度下降,HC和CO也趋于下降，但NOx排放显著增加；推迟供油提前角，可以使NOx排放降低，但碳烟有上升趋势，HC和CO排放增加。所以，采用富氧燃烧时必须同时推迟供油提前角，才能获得较低的排放量组合。