生物制气-柴油双燃料发动机NOx计算模型

采用气化炉热解气化各种农林废弃的生物质，产生可燃生物制气，作为双燃料发动机的主要燃料。双燃料发动机由单缸、四冲程、水冷、直喷式柴油机改装，生物制气通入发动机进气管，在进气过程中吸入气缸。在油滴蒸发准维燃烧模型的基础上，结合单区模型和详细化学反应动力学机理，建立生物制气-柴油双燃料发动机的NOx生成模型，计算结果与试验结果吻合较好。供油提前角提前，生物制气-柴油双燃料发动机NOx排放量增加；引燃柴油量减小时，NOx排放量减小。

Simulation of NOx Emission in Biogas Diesel Dual-Fuel Engine

Biogas can be made from various kinds of agricultural and forestry residues by a gasifier,and can be used as the main fuel of a biogas diesel dual-fuel engine ignited by diesel fuel.The dual-fuel engine is modified from a single cylinder,four-stroke,water-cooled,direct injection diesel engine.The biogas is induced to the cylinder through intake pipe during the intake process.A combustion and NO_x formation model for biogas diesel dual-fuel engine is established.The model combines the single-zone model and the quasi-dimensional spray combustion model based on hiroyasu's model and the detailed chemical kinetics of NO_x formation.The NO_x emission at various speeds and loads are measured.The simulated and measured NO_x emissions show good agreement.The relationship between the NO_x emission performance and the operating parameters,such as engine speed and fuel pilot quantity are studied by using this model.NO_x emission of the biogas diesel dual-fuel engine increases with the increase of pilot fuel quantity and the advancement of fuel delivery advance angle.