Application of Air-assist Injector on Semi-direct Injection System.

• Main Authors: Chih-Hau Kao, 高志豪
• Other Authors: Yuh-Yih Wu
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/e69a5u

碩士 === 國立臺北科技大學 === 車輛工程系所 === 96 === In this paper, the compressed air is used to improve the atomization of traditional injector, then used high speed camera to observes the fuel spray pattern and the effect fuel atomization. Result shows the atomization will lower while tube diameter and tube length of the adaptor increase. The modified intake manifold increases the swirl ratio to 2.032 and 3.5 at engine experiment. The combined air-assist injector makes the traditional PFI system into SDI system, and increasing the lean misfire limit and decreasing fuel consumption. The experimental results show the lean limit increases by the fuel injection during intake valve opened, the swirl ratio and the fuel atomization also increase. The intake swirl ratio is increased to 3.5 and the air flow rate of assist air is 20 L/min. The atomization of injector is improved and the lean misfire air-fuel ratio limit is increased from 17.1 to 23.7. The break specific fuel consumption and coefficient of variation are reduced significantly.