Experimental investigation of the effect of orifices inclination angle in multihole diesel injector nozzles. Part 2 – Spray characteristics

• Published in: Fuel (Guildford) 2018-02, Vol.213, p.215-221
• Main Authors: Payri, R., Salvador, F.J., De la Morena, J., Pagano, V.
• Format: Article
• Language: English
• Subjects: Combustion; Combustion chambers; Density; Diesel; Effects; Inclination; Inclination angle; Nozzle; Nozzles; Orifices; Penetration; Pressure vessels; Room temperature; Spray; Spray characteristics; Statistical correlation; Temperature; Velocity; Visualization
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/j.fuel.2017.07.076

•Influence of nozzle included angle on spray penetration was evaluated.•Higher angle induces lower spray penetration, especially at high injection pressure.•Spray penetration results are mostly linked to nozzle outlet velocity.•Correlation of spray penetration in terms of hydraulic coefficients is proposed. Diesel spray development is a key research topic due to its impact on the combustion characteristics. On the current paper, the effect of the orifices inclination angle on the spray penetration characteristics is evaluated. For this purpose, three nozzles with included angles of 90, 140 and 155° are selected. Visualization tests are performed on a room-temperature constant-pressure vessel pressurized with a high-density gas (SF6), in order to reproduce the density conditions inside the combustion chamber at the start of the injection event. Both frontal and lateral Mie-scattering visualization are used, depending on the particular nozzle configuration. Results show how the spray penetration is slower as the inclination angle increases, which is linked to its lower nozzle outlet velocity. A statistical correlation of the spray penetration as a function of the area and velocity coefficients is obtained and discussed.