Taylor bubble velocity measurement by using image processing

The purpose of this study is to generate two-phase flow patterns and to obtain a flow pattern map for two phases as water and air in a vertical pipe which is made of transparent Plexiglas. The pipe specification is 50 mm diameter and 390 cm length. In this attempt the average velocity of the Taylor bubble will be calculate. In order to facilitate this research work, a two phase flow was designed, built and adjusted at Tarbiat Modares University Two-phase flow laboratory. Three flow patterns as bubbly, slug and churn flow are generated and examined for 320 runs of different superficial velocities of air and water. A seven-layer distributor with the ability to change the number of bubbles produced is used to create a bubbly flow pattern at the air inlet. The effect of the superficial velocities of each phase on the flow pattern was evaluated and a flow pattern map was presented for 320 different data. By processing the images obtained from the high-speed camera, the average Taylor bubble velocity was calculated for different flow conditions with uncertainty in calculating the velocity. Also, for 5 different velocities of the liquid phase, a diagram of the average velocity of Taylor velocity with increasing gas velocity was drawn and compared with the Nicklin correlation which can be found in the literature