A model for fuel spray penetration

• Published in: Fuel (Guildford) Vol. 80; no. 15; pp. 2171 - 2180
• Main Authors: Sazhin, S.S., Feng, G., Heikal, M.R.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.12.2001; Elsevier
• Subjects: Applied sciences; Diesel engines; Droplet break-up; Energy; Energy. Thermal use of fuels; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Exact sciences and technology; Fuel spray; Furnaces. Firing chambers. Burners; Liquid fuel burners and combustion chambers; Two-phase flow; Droplet break-up; Fuel spray; Diesel engines; Two-phase flow; Two phase flow; Diesel fuel; Theoretical study; Diesel engine; Droplet; Fuel injection; Spray burner; Fuel injector
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/S0016-2361(01)00098-9

A new model for fuel spray penetration (location of spray tip) is suggested and validated against available experimental data. Simple analytical expressions for fuel spray penetration are derived in two limiting cases: the initial stage and the two-phase flow regime. At the initial stage, the effects of droplet drag and entrainment of air are accounted for. In the case of the two-phase flow, it is assumed that the spray droplets have the same velocities as the entrained air. The characteristic time of droplet break-up in the spray is estimated for both bag and stripping break-up mechanisms. For realistic diesel spray parameters, the droplet break-up takes place almost immediately after the droplets leave the nozzle. This leads to a considerable shortening of the initial stage and a rapid conversion of the flow to the two-phase stage. This allows the analysis to be restricted to the two-phase flow approximation for this type of spray. The expressions for spray penetration derived in this paper give more accurate predictions compared with those suggested earlier.