Dimethyl ether spray characteristics under engine-like conditions
1.School of Automobile and Traffic Engineering, Wuhan University of Science and Technology, Wuhan, Hubei 430081, China; 2.Graduate School of Science and Engineering, Ibaraki University, Hitachi, Ibaraki 3160036, Japan
Abstract：The background scattering method was used to only take liquid state spray videos. The actual pressure and the temperature conditions in turbocharged engines were simulated in a constant volume vessel, and the DME spray characteristics were investigated with ultra-high speed camera. The influences of environment temperature and pressure, injection pressure and nozzle diameter on spray characteristics of DME were also investigated. The results show that the spray penetration distance increases with the increasing of injection pressure and nozzle diameter. Under the conditions with high temperature and high pressure in turbocharged engine environment, the spray penetration distance decreases when the ambient gas density and the temperature are increased. The liquid drops appear around DME sprays only at normal temperature. Compared with diesel spray, DME spray evaporates more quickly. For both of the two kinds of spray, the outline parts show unregulated wave shape.The diesel spray is broken into particles constantly with droplet splitting, while the DME spray division is directly started from the main spray rapid evaporation.
2014, Vol. 35 
