An Investigation of the Influence of Back Pressure on the Diffusion of Mass and Momentum of Fuel in Diesel Spray

The influence of the back pressure on the diffusion of mass and momentum of the fuel in the diesel spray is investigated and reported in this paper. Analytical models were proposed to depict the similarity profiles for the distribution of velocity and mass of the fuel in the diesel spray injected into stagnant atmosphere maintained at different back pressures and ambient temperature. It is conclusively shown that the proposed models are superior to Abramovich and Albertson models so far as the spray situation is concerned. The Schmidt number, σ_f, varied from 0.806 to 0.430 when the injection pressure was varied from 100 to 200 atm and the back pressure from 1 to 10 atm. It is confirmed that mass diffuses faster than the momentum, the rate of diffusion increasing with the increase in injection pressure and the back pressure.