Effect of bubble diameter size on prediction of flow pattern in Euler–Euler simulation of homogeneous bubble column regime

•An Euler–Euler approach is used for various bubble sizes at different superficial gas velocities.•The correct selection of bubble size in numerical setting enhances the accuracy of predicted results.•At different bubble column heights, the average bubble size changes.

Determining the bubble size in a numerical setting plays an important role in accurate prediction of flow pattern and gas dynamics in a bubble column rector. This paper employs the Eulerian–Eulerian method to numerically investigate the sensitivity study of bubble size on the accuracy of numerical method for different superficial gas velocities. The present experimental observation and prior experimental, numerical and mathematical correlation results are used for comparison with present CFD study. In addition, the experimental set-up is used to show the bubble formation and rising from a single sparger and effect of bubble size and shape on the flow regime for various velocities. The result shows that 3 mm bubble diameter is a reasonable size for prediction of flow pattern near the bulk region for superficial gas velocities ranged 0.0025–0.015 m/s. As the homogeneous regime changes to heterogeneous one, the interaction rate between bubbles increases and bubbles travel with various sizes, velocities and shapes. In this case the selection of one bubble diameter for entire numerical study cannot be accurate.