Digital image processing techniques for the analysis of fuel sprays global pattern

2017 International Conference on Material Engineering and Advanced Manufacturing Technology

Zakaria, Rami^1 ; Bryanston-Cross, Peter^2 ; Timmerman, Brenda^2

Department of Mechanical System Engineering, Hansung University, Seoul, Korea, Republic of^1

School of Engineering, Warwick University, Coventry, United Kingdom^2

关键词: Digital image processing technique;    Discharge velocity;    Dispensing systems;    Fuel injection systems;    Injection frequencies;    Optical diagnostic systems;    Particle image velocimetries;    Testing conditions;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/282/1/012001/pdf
DOI  :  10.1088/1757-899X/282/1/012001

来源: IOP

【 摘 要 】

We studied the fuel atomization process of two fuel injectors to be fitted in a new small rotary engine design. The aim was to improve the efficiency of the engine by optimizing the fuel injection system. Fuel sprays were visualised by an optical diagnostic system. Images of fuel sprays were produced under various testing conditions, by changing the line pressure, nozzle size, injection frequency, etc. The atomisers were a high-frequency microfluidic dispensing system and a standard low flow-rate fuel injector. A series of image processing procedures were developed in order to acquire information from the laser-scattering images. This paper presents the macroscopic characterisation of Jet fuel (JP8) sprays. We observed the droplet density distribution, tip velocity, and spray-cone angle against line-pressure and nozzle-size. The analysis was performed for low line-pressure (up to 10 bar) and short injection period (1-2 ms). Local velocity components were measured by applying particle image velocimetry (PIV) on double-exposure images. The discharge velocity was lower in the micro dispensing nozzle sprays and the tip penetration slowed down at higher rates compared to the gasoline injector. The PIV test confirmed that the gasoline injector produced sprays with higher velocity elements at the centre and the tip regions.