Visualization Experimental Study On Spray Characteristics Of Aviation Kerosene

With the gradual opening of the low altitude area,the general aviation field has been developing rapidly,and emission regulations are becoming more stringent.As a reciprocating aero engine fuel,the existing aviation gasoline is no longer suitable for today's emission requirements.Similarly,in the military field,for the sake of safety and management convenience,there is an urgent need for military fuel to be single.Therefore,it is necessary to find a kind of fuel that can reduce harmful gas emissions as far as possible under the premise of improving engine performance.The physical and chemical properties of aviation kerosene are between gasoline and diesel,which are more stable and safer than gasoline,and viscosity and density are smaller than diesel fuel,which is favorable for fuel droplet atomization.The atomization of engine fuel spray directly affects the combustion effect.Therefore,understanding its spray mechanism and spray characteristics is very important for improving fuel economy and improving emissions.In order to explore the difference of spray characteristics of different fuels,explore the feasibility of the application of aviation kerosene on diesel engine,develop new fuel and improve the fuel economy of the engine,the visualization experiment on spray characteristics of aviation kerosene and diesel oil is carried out in this paper.The difference between the two kinds of fuel in the aspects of spray breaking,evaporation and mixing gas is compared and analyzed,which provides the basic theoretical basis for the development of reciprocating compression ignition engines,which are used as fuel for aviation kerosene.In this paper,using the existing visualization experimental platform of spray combustion,using direct high-speed photography and schlieren high-speed photography,the spray characteristics of two kinds of fuel are visualized under different conditions of non evaporation environment and evaporation.Then,the result data are processed by the self-compiled MATLAB program,and the macro parameters such as penetration distance,cone angle,projection area and volume are calculated.The experimental results show that the variation trend of the two kinds of fuel is the same in the non evaporative state,and the difference is not significant,and the differences in physical and chemical properties of the two kinds of fuel are not reflected.When the background pressure is increased,although the spray shape will become short,but because of the increase of gas volume,it can promote oil and gas mixing.When the injection pressure is increased,the droplet evaporation rate will increase and the spray penetration distance will increase.It is necessary to take into account the optimization of the combustion chamber.The increase of background temperature can accelerate the atomization of fuel and promote the mixing of oil and gas.And at high temperature,the difference of physicochemical properties of diesel and aviation kerosene diesel and aviation kerosene obviously shows,and the effect of vaporization and atomization of aviation kerosene is obviously better than that of diesel.