The Research Of Emulsifying Combustion On Performance Of Turbocharged Diesel

With the increasingly serious environmental problems,the emission regulations formulated by various countries have become increasingly stringent.In order to reduce the emission of NOx effectively,inhibit the generation of Soot,and optimize the combustion process,this paper studied the water blending combustion technology and analysed the influence of water blending technology of emulsified oil and intake air humidifying technology on the combustion process parameters and emission performance of diesel engine.Firstly,a TBD234V6 turbocharged and intercooled diesel engine was used as the prototype,and the AVL-FIRE simulation software was used to establish a 3D model of the whole combustion chamber.After the validity of the model was verified,the research about the effects of water blending emulsification and intake air humidification were carried out,and the gray decision theory and combination weight method were used to determine the water fuel radio and water blending radio.Simulation results showed that:under the rated conditions,the best water fuel radio for this diesel was 10%.Compared with the original machine,the engine power reduction was 5.5%,the fuel consumption rate was reduced by 7.03%,NOx emissions was reduced by 36.48%,Soot emissions by 7.53%.The best water blending radio was 0.5.Compared with the original machine,the engine power increasion was 4.51%,the fuel consumption rate was reduced by 5.92%,NOx emissions was reduced by 46.1%,Soot emissions by 34.87%.Secondly,by comparing the two water blending combustion technologies,the water blending technology of emulsified oil was selected to analyze its influence on the performance of diesel engine under variable working conditions.The results showed that the pressure,temperature and power decreased with the increase of water fuel radio under the same load.Under the same water-incorporation ratio,the pressure and power increased with the increase of load,the temperature decreased first and then increased with the increase of the load,and the minimum value was at 50%of the load,in this case the temperature decreased by 23.03%.In terms of fuel consumption ratio,the minimum value was at 10%water fuel radio under 50%and 75%load,and the maximum fuel economy was 1.47%and 3.22%,respectively.Under 100%load,the minimum value was reached when the water fuel radio was 20%,and the maximum fuel economy was 8.77%.Then,the optimal condition for the stability of the emulsified oil was determined by the emulsification test and the microscopic observation.The HLB of the oil-water system was 5.8.2.2%span80,77.8%ween 80 and 20%sodium dodecylbenzenesulfonate were blended to get the emulsifier at a concentration of 2%.Emulsifying time should be less than 10min;Suitable temperature range was 20～40℃.Finally,based on the existing test conditions,the water emulsified fuel system was designed,and the rig can be tested under appropriate conditions.