Analysis of horizontal slug translational velocity based on the image processing technique

Slug flow is a common flow regime that occurs in chemical industries, petroleum and power generation. The aim of this paper is to investigate the correlation between the slug bubble translational velocity and the air-liquid superficial velocity based on the development of a new image processing procedure. In this paper, the slug bubble contour and translational velocity were measured in the 15 mm inner diameter pipe. In order to observe the interfacial behavior of air-liquid, both of the liquid and air superficial velocity were set to $0.3 \sim0.9 m/$s. The adopted image processing has succeeded to detach the dispersed bubble from the slug bubble tail, which overcome the challenge for the visualization of slug bubble. Moreover, the mechanisms of the disappearance of slug bubble tail are analyzed based on the interfacial behavior. Finally, the data results display that the slug translational velocity in experiment is lower than the model predicted velocity at the boundary of bubbly flow and slug flow.