Bubble dynamics and pressure drop in a downward flow in a horizontal bundle of rods during short-time injection

The study is devoted to the investigation of pressure fluctuations in a downward flow in a rectangular channel (80×152×440 mm) with a horizontal pipe bundle during a short-time injection of a single gas bubble. The fluid flow velocity ranged from 0 to 0.7 m/s. The gas flowed into the channel from a fixed volume of 30 ml with an injection pressure in the range of 2–12 bar. It was found that an increase in injection pressure leads to an increase in the amplitude of oscillations. It was also established that the fluid flow rate does not significantly affect the pressure change in the system in this injection pressure range.