Recent Patents on Engineering, Vol 12, No 3 (2018)

Font Size:  Small  Medium  Large

Numerical Investigations on Influence of Bubble Velocity, Gravity Level and Bubble Coalescence on Liquid Turbulence Modulation in Horizontal Channel Bubbly Flow

Dr. Mingjun Pang, Mr. Zhan Zhang, Mr. Yang Fei, Mr. Yidan Xu

Abstract


Background: Bubbly flows can frequently be seen in engineering fields such as fermentation reactions, floatation of minerals, drag reduction by bubbles, etc. The physical parameters often change in industrial processes so it’s essential to perform deep studies on the influence of gas- and liquid-phase parameters on the liquid turbulence. Objective: Through studying deeply the liquid turbulence modulation by the bubble injection with changing bubble velocity, gravity magnitude and considering if the bubble coalescence happens, it is hoped to obtain some physical laws on the liquid turbulence flow laden with bubbles so as to guide the design of patents on the drag reduction system by bubbles. Methods: The bubbly turbulent flows are investigated with the numerical method, the mixture model is chosen as the multiphase flow model, and the velocity field of the turbulent flow is solved by Reynolds stress model. Results: The present results show that the bubble velocity has very little influence on the liquid-phase turbulence; gravity magnitude has the definite influence on the liquid-phase turbulence, and the influence of the bubble injection on the liquid-phase turbulence under normal gravity is far greater than that under microgravity; in addition, only when the bubble volume fraction is sufficiently high, the bubble coalescence has the significant influence on the liquid-phase turbulence. Conclusion: The influence of gravity on the bubble distribution and the liquid-phase turbulence is important, and the bubble coalescence causes the definite influence on the liquid turbulence modulation when the bubble volume fraction is high enough.

Refbacks

  • There are currently no refbacks.