A study on the spray characteristics of CRDI system with injection pressure

분사압력에 따른 CRDI 분사계의 분무특성에 관한 연구

KIM, Sang-Am;WANG, Woo-Gyeong;YANG, Jung-Kyu

  • Received : 2016.01.07
  • Accepted : 2016.01.19
  • Published : 2016.02.28


Injection rate, injection quantity and injection timing of fuel are controlled precisely by electric control in CRDI system. Particularly, injection rate being influenced with injection pressure affects to spray characteristics and fuel-air ratio, so it is a very important factor in diesel combustion. In this study, injection rates in accordance with injection pressure at a constant ambient pressure were measured with Zeuch's method. Under the same condition, non-evaporating spray images were taken with a high speed camera and analyzed carefully with Adobe Photoshop CS3. Macroscopic spray characteristics and breakup processes in the spray could be found from the examined and analyzed data. Injection start time and injection period were practically affected with injection pressure. Also, initial injection rate, spray penetration, spray angle and breakup of high density droplets region in the spray were affected with injection pressure. The results and techniques of spray visualization and injection rate measurement in this study would be practically effective to study a high pressure diesel spray for common rail direct injection system.


Injection rate;Penetration;Spray angle;Breakup;High density droplet area


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