Effects of Injection Nozzle Geometry on Spray Characteristics for Direct Injection Diesel Engines

[EN] The purpose of this study is to improve the spray characteristics of a direct injection Diesel nozzle. Spray atomization of the multi-hole atomization enhancement nozzle, which was invented in previous studies, is explored. The aim is to improve and obtain excellent spray characteristics. The e...

Descripción completa

Detalles Bibliográficos
Autores: Tamaki, Nobushige, Harada, Takato
Tipo de recurso: capítulo de libro
Fecha de publicación:2017
País:España
Institución:Universitat Politècnica de València (UPV)
Repositorio:RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia
Idioma:inglés
OAI Identifier:oai:riunet.upv.es:10251/100370
Acceso en línea:https://riunet.upv.es/handle/10251/100370
Access Level:acceso abierto
Palabra clave:Atomization
Diesel engine
Spray characteristics
Injection nozzle
Cavitation
Descripción
Sumario:[EN] The purpose of this study is to improve the spray characteristics of a direct injection Diesel nozzle. Spray atomization of the multi-hole atomization enhancement nozzle, which was invented in previous studies, is explored. The aim is to improve and obtain excellent spray characteristics. The effects of different nozzle geometries and dimensions on spray characteristics are investigated, including chamfered and rounded nozzle hole inlets and a multi-hole atomization enhancement nozzles. It is found that the multi-hole atomization enhancement nozzle with a rounded chamfered inlet is effective in achieving a high-dispersion spray, a large spray angle and small droplets. However, it should be noted that the spray is significantly atomized and a large number of small droplets as suspended as a mist. The photographic images of the spray are taken against a white background and the boundaries between the ejected spray and the background are indistinct. Furthermore, the breakup length is short at 3 mm for a hole diameter of 0.3 mm, the spray angle is about 70° and the Sauter mean diameter decreases dramatically to 15 μm at a low injection pressure of 10 MPa