Experimental Study On Influence Of Oxygen-rich Air Combustion On Dynamic And Emission Performance Of Natural Gas/Gasoline Binary Engine

Using oxygen-rich air to support combustion can decrease ignition point of the fuel, accelerate combustion speed, facilitate complete combustion, enhance temperature of blaze, decrease exhaust, make much more heat available and reduce superfluous air coefficient, it has superior performance in energy saving and environmental protection, has been widely applied in many situation which take gas, oil and coal as fuel, but both overseas and domestic researches didn't concentrated on oxygen-rich air combustion-supporting techniques that applied to internal-combustion engine. Because of its advantages on economy, resource and emission performance, NGV developed rapidly. Domestic NGV engines are usually changed from gasoline engine, belong to homogeneous pre-mixed NGV engine. As a result of its fuel supply manner, its dynamic performance decline, and this is an obstacle to popularizing and applying NGV. It is feasible to enhance gasoline-gas binary engines'dynamic and emission performance by adopting oxygen-rich air combustion-supporting techniques.This paper firstly studied on the theoretical influence of oxygen concentration on combustion performance of gasoline and natural gas. By calculating the theoretical air fuel ratio, theoretical quantity of heat of mixed gas and theoretical combustion temperature, it can be conclude that theoretical air-fuel-ratio, quantity of heat of mixed gas and combustion temperature were increased along with the oxygen concentration growing; indicated and effective power of the engine were enhanced; fuel consuming rate were declined; part of emission performances were improved.Aim at the results of theoretical analysis, this paper carries out an experiment to prove them. Power, torque, fuel consuming rate and concentration of emissions were test in the experiment to study the influence of oxygen concentration under different working condition while using gas or gasoline. it can be conclude that as the oxygen concentration developed, power and torque of the engine were enhanced at every working condition, and fuel consuming rate were decreased; At the best oxygen concentration range(23%~25%), while using natural gas, power has about 7.8 to 12.5 percent and torque has 8.1 to 11.8 percent enhancement, fuel consuming rate has 5.4 to 11.4 percent decrease; While using gasoline, power has 9.6 to 16.3 percent and torque has 9.4 to 16.7 percent enhancement, fuel consuming rate has 7.2 to 11.4 percent decrease; Concentration of hydrocarbon and carbon monoxide were declined at about...