Behaviors of Spray Droplets with and without Flat Wall Impingement Univ of Hiroshima

Format:

Book

Conference/Event

Author/Creator:

CHANG, Feixiang, author.

Contributor:

LUO, Hongliang

Nishida, Keiya

Ogata, Youichi

Zhan, Cheng

Conference Name:

15th International Conference on Engines & Vehicles (2021-09-12 : Capri, Italy)

Language:

English

Physical Description:

1 online resource cm

Place of Publication:

Warrendale, PA SAE International 2021

Summary:

Fuel spray impingement on the combustion chamber wall cannot be avoid in direct injection gasoline engines, resulting in insufficient combustion and unburned hydrocarbon/soot emissions from the engines. And the microscopic characteristics of the impinging spray have a close relation with the fuel film formation, which has a direct effect on the engine performance and emissions. Therefore, figuring out the droplet behaviors of the impinging spray is significantly important for improving the engine performance and reducing emissions. However, the microscopic characteristics of the impinging spray have not been deeply understood and the differences between the impinging and free spray are seldom mentioned in previous study. Therefore, particle image analysis (PIA) technique was applied to detect the microscopic characteristics at the capture location in order to track the droplet behaviors of the spray tip during the propagation process. Toluene as the test fuel is injected by a mini-sac injector with a single hole in this work. Firstly, the difference of the impinging and free spray is compared at three spray tip locations. Secondly, the droplet behaviors of the impinging spray were further acquired at five locations. Results showed that compared to the free spray, the impinging spray had smaller velocities at all penetration locations, which was caused by the interaction between spray and impingement wall. And the droplet diameter and Weber number (We) of the impinging and free spray were also analyzed. Moreover, droplet spatial distribution of the impinging spray was investigated. And the "secondary droplet" behavior was estimated by dimensionless numbers. The "secondary droplets" almost located at the "splash region" according to Bai models. Most of the "secondary droplets" splashed from the cylinder wall due to the strong interaction. And some droplets located at the "spread region", which indicated "secondary droplets" would deposit on the cylinder wall

Notes:

Vendor supplied data

Publisher Number:

2021-24-0058

Access Restriction:

Restricted for use by site license