Numerical and Experimental Design Study of a Regenerative Pump

Abstract

This paper presents the use of a commercial CFD code to simulate the flow-field within the regenerative pump and compare the CFD results with new experimental data. Regenerative pumps are the subject of increased interest in industry as these pumps are low cost, low specific speed, compact and able to deliver high heads with stable performance characteristics. The complex flow-field within the regenerative pump represents a considerable challenge to detailed mathematical modelling. This paper also presents a novel rapid manufacturing process used to consider the effect of impeller geometry changes on the pump efficiency. Ten modified impeller blade profiles, relative to a standard radial configuration, were evaluated. The CFD performance results demonstrate reasonable agreement with the experimental tests. The CFD results also demonstrate that it is possible to represent the helical flow field for the pump which has only been witnessed in experimental flow visualisation until now. The ability to use CFD modelling in conjunction with rapid manufacturing techniques has meant that more complex impeller geometry configurations can now be assessed with better understanding of the flow-field and resulting efficiency.

Regenerative flow pumps, blowers and compressors – A review

“…Researchers have used blade numbers varying from as low as 12 16 to as high as 150 16,21 These are extreme numbers but most of the other researchers used blade numbers in the range of and around 30–50. 6,8,9,19,20,22–45 No particular trend is observed indicating the dependency of the number of blades on the working fluid. Table 1 shows the number of blades investigated by various researchers.…”

“…Unsteady flow is useful to capture the flow in the intricate paths. Quail et al., 25,27,28,30 Badami and Mura, 32 Mekhail et al., 52 Griffini et al., 56 Zhang et al., 41 and Fathi et al. 43 have used a steady flow model.…”

“…Quail et al. 25,27,30,59 in their various works, used CFD to predict the fluid flow pattern in a regenerative flow pump, especially the circulatory motion observed during experiments. They also compared the 1-D (Analytical) and 3-D CFD models and concluded that though CFD consumes more time and effort than 1-D models, it is worthwhile considering the accuracy of the results.…”

“…22 Quail et al. 25,28,59 conducted extensive experimental work on regenerative flow pumps. They estimated the pressure developed, flow coefficient, efficiency for radial and optimized blades and compared with CFD predictions.…”

Regenerative liquid ring pumps review and advances on design and performance

“…This makes the RLR pump able to handle gases or a mixture of gas and liquid. Under the same conditions a centrifugal pump would be subjected to cavitation as the bubbles will collapse violently due to the sudden increase in pressure [3,48]. The amount of entrained gases the RLR pump can handle varies but numbers ranging from 20-50% have been reported [48,51].…”