Investigation of Spray Behaviour Simulation to Predict Spray Tip Penetration Under Ultra-High Injection Pressure

Abstract

The spray characteristics, in particular, the spray tip penetration and atomization of the droplet are known to affect the fuel combustion in the diesel engine. Researchers have enough understanding of the diesel spray characteristics, but less frequent literature is available for biodiesel with ultra-high injection pressure. The non-evaporating spray simulation has been carried out for a single-hole fuel injector nozzle with a 0.16 mm diameter. The diesel fuel has been considered to be injected with 300 MPa injection pressure. The discrete phase model (DPM), which is based on the Lagrangian drop Eulerian fluid method, is used to simulate spray characteristics. The discrete random walk (DRW) model has taken into account the turbulent diffusion of the spray droplet. The spray tip penetration (STP) length has been calculated with the Kelvin–Helmholtz Rayleigh–Taylor (KHRT), Wave and Stochastic Secondary Droplet (SSD) spray breakup models and compared with the existing experimental data. The Wave model and experimental findings show good agreement. Three different nozzle diameters (0.16 mm, 0.25 mm and 0.3 mm) have been used to compare the L/d ratio with STP length. Finally, the spray formation with biodiesel exhibits slightly better spray penetration but suppressed atomization as compared to diesel fuel.