SCI和EI收录∣中国化工学会会刊

Chin.J.Chem.Eng. ›› 2015, Vol. 23 ›› Issue (1): 262-267.DOI: 10.1016/j.cjche.2014.10.009

• ENERGY, RESOURCES AND ENVIRONMENTAL TECHNOLOGY • Previous Articles     Next Articles

Instability and breakup of cavitation bubbles within diesel drops

Ming Lü, Zhi Ning, Kai Yan, Juan Fu, Chunhua Sun   

  1. College of Mechanical and Electrical Engineering, Beijing Jiaotong University, Beijing 100044, China
  • Received:2013-04-18 Revised:2013-09-15 Online:2015-01-24 Published:2015-01-28
  • Contact: Zhi Ning
  • Supported by:

    Supported by the National Natural Science Foundation of China (51276011), the National High Technology Research and Development Program of China (2013AA065303), Beijing Municipal Natural Science Foundation of China (3132016), and the Opening Foundation of State Key Laboratory of Engines (K2013-3).

Instability and breakup of cavitation bubbles within diesel drops

Ming Lü, Zhi Ning, Kai Yan, Juan Fu, Chunhua Sun   

  1. College of Mechanical and Electrical Engineering, Beijing Jiaotong University, Beijing 100044, China
  • 通讯作者: Zhi Ning
  • 基金资助:

    Supported by the National Natural Science Foundation of China (51276011), the National High Technology Research and Development Program of China (2013AA065303), Beijing Municipal Natural Science Foundation of China (3132016), and the Opening Foundation of State Key Laboratory of Engines (K2013-3).

Abstract: Amodified mathematical model is used to study the effects of various forces on the stability of cavitation bubbles within a diesel droplet. The principal finding of the work is that viscous forces of fluids stabilize the cavitation bubble, while inertial force destabilizes the cavitation bubble. The droplet viscosity plays a dominant role on the stability of cavitation bubbles comparedwith that of air and bubble. Bubble-droplet radius ratio is a key factor to control the bubble stability, especially in the high radius ratio range. Internal hydrodynamic and surface tension forces are found to stabilize the cavitation bubble, while bubble stability has little relationship with the external hydrodynamic force. Inertia makes bubble breakup easily, however, the breakup time is only slightly changed when bubble growth speed reaches a certain value (50 m·s-1). In contrast, viscous force makes bubble hard to break. With the increasing initial bubble-droplet radius ratio, the bubble growth rate increases, the bubble breakup radius decreases, and the bubble breakup time becomes shorter.

Key words: Stability, Diesel droplet, Cavitation bubble, Secondary breakup

摘要: Amodified mathematical model is used to study the effects of various forces on the stability of cavitation bubbles within a diesel droplet. The principal finding of the work is that viscous forces of fluids stabilize the cavitation bubble, while inertial force destabilizes the cavitation bubble. The droplet viscosity plays a dominant role on the stability of cavitation bubbles comparedwith that of air and bubble. Bubble-droplet radius ratio is a key factor to control the bubble stability, especially in the high radius ratio range. Internal hydrodynamic and surface tension forces are found to stabilize the cavitation bubble, while bubble stability has little relationship with the external hydrodynamic force. Inertia makes bubble breakup easily, however, the breakup time is only slightly changed when bubble growth speed reaches a certain value (50 m·s-1). In contrast, viscous force makes bubble hard to break. With the increasing initial bubble-droplet radius ratio, the bubble growth rate increases, the bubble breakup radius decreases, and the bubble breakup time becomes shorter.

关键词: Stability, Diesel droplet, Cavitation bubble, Secondary breakup