An experimental study on the effect of gas injection configuration on flow characteristics in high viscosity oil columns

Abstract

Gas‐viscous liquid bubbly and slug flow are very common in petroleum, chemical, bioengineering, polymer, and food processing. However, there is a major knowledge gap in two‐phase flow research in the design of gas injectors/distributers in very high viscosity oil systems. The present study investigates the effect of gas injection methods in columns containing very high viscosity oils (i.e., realistic liquids), and more specifically using 360 Pa · s viscosity oil in a 240‐mm diameter column. The effects that the radial positioning, number of gas nozzles, and their distance from each other have on the structure of the flow in viscous liquids are presented in detail. Electrical capacitance tomography (ECT) is used to extract experimental data. Void fraction, bubble velocity, frequency, liquid film thickness, and bubble length were measured and analyzed at different radial gas injection positions. It has been observed that bubble length increases significantly by 0.3 m when the injection nozzle is located next to the wall of the pipe. Bubble velocity and length also increase by 0.217 m/s and 3.6 m, respectively, with increasing gas flowrate when multiple injection points are used. Increasing the distance between the gas injection points increased bubbles' length by 1.2 m. Bubbles' velocity and frequency (at higher gas flow rate) were also increased.

Effects of guide holes on the performance of a vertical turbo air classifier

“…Its main functions include flow guidance, flow rate adjustment, flow field optimization, and efficiency improvement. [1][2][3][4][5][6] The turbo air classifiers are the typical fluid machinery to prepare ultra-fine powder in various industries because of their advantages of simple operation, adjustable particle size, high efficiency, and low energy conservation. [7][8][9] For the classifier, the guide parts can be used to guide the fluid and improve the flow field distribution.…”