Experimental Investigation On Spray And Evaporation Characteristics Of Ethanol Diesel And Ethanol Diesel Nanofuel

As a kind of clean and renewable energy,ethanol has a wide range of sources and low cost.Blending with diesel in engines can effectively reduce the dependence on traditional fossil fuel,improve combustion efficiency and reduce emissions of soot and other incomplete combustion products.The addition of nanoparticles can further reduce the emission of pollutants such as NOx and CO during the combustion process of internal combustion engines.It is of great significance to study the spray characteristics of ethanol diesel blended with nanoparticles and the evaporation process of the mixed droplets for its application in internal combustion engines.The main work of this paper is as follows:Evaporation sequence diagrams of diesel droplets mixed with different proportions of ethanol were measured on the atmospheric and constant temperature single droplet evaporation experiment platform.MATLAB was used to write a program to calculate the mixed droplet diameter in the evaporation sequence diagram,and the expansion intensity and broken intensity of mixed droplets were calculated based on the diameter value.Results showed that there were four droplet breakup modes in the evaporation process of mixed droplets.The vapor cloud phenomenon was observed in the evaporation image of the mixed droplet of DE60.According to the change of the normalized diameter of the mixed droplet,the evaporation process of the droplet was divided into three stages:the droplet heating stage,the fluctuation evaporation stage,and the equilibrium evaporation stage and the droplet diameter change in the equilibrium evaporation stage satisfies the d2 law.In addition,the calculation results showed that the droplet expansion intensity and broken intensity increase at first and then decrease with the increase of ethanol blending ratio,which is the same as the experimental observation.The spray penetration distance,spray cone angle,spray tip velocity and spray projection area of ethanol diesel blended with different concentrations of CeO2 nanoparticles were measured on a high pressure common rail experimental platform.The experimental results showed that adding nanoparticles in ethanol diesel oil can increase the spray penetration distance,expand the spray cone angle and increase the spray projection area.In addition,the addition of nanoparticles can also shorten the critical breaking time of the fuel jet,increase spray area,promote the mixing of fuel and air.Through comparative analysis,it is found that the spray parameters of DE20CE50 are almost the same as that of pure diesel.