Numerical Study on the Influence of Different Operating Conditions on Mixing Uniformity of the Helical Gear Pump Mixer

Abstract

The uniformity of the gelatin solution and water mixing process is a critical factor in the performance of helical gear pump mixers that affects pump efficiency. In this study, we investigate the impact of water inlet velocity and rotational speed on the helical gear pump mixer. A numerical model of the helical gear pump mixer is established using Simerics MP+ 5.2.15 software. By varying the water inlet velocity from 0.159 m/s to 1.272 m/s and the rotational speed from 8 rpm to 50 rpm, we obtained volume fraction distributions of water in different sections of the helical gear pump mixer. The simulation results show that the high water inlet velocity causes the water and gelatin solution in the mixing tank to not mix fully. When the inlet speed is 0.318 m/s, the mixing uniformity of the gelatin solution and water in the mixing tank is effectively promoted, and the maximum volume fraction of water in the water-rich region is reduced by 70.24%. In poor water regions, the maximum volume fraction of water increased by 9.25 times. Furthermore, within a certain range, increasing the rotational speed of the helical gear pump promotes the faster transport of water to the back of the mixing tank, leading to reduced non-uniformity in the gelatin solution and water mixing process. These findings provide valuable insights for enhancing mixing uniformity in helical gear pump mixers.