Comparative Study of the Performance Characteristics of Annular Jet Pumps Conveying Newtonian and Shear-Thinning Non-Newtonian Fluids

This study investigates the factors influencing the performance characteristics of annular jet pumps (AJPs) conveying non-Newtonian fluids, to enhance their suction capability for marine organisms such as jellyfish, which exhibit properties close to non-Newtonian fluids. Based on the power-law fluid model, realizable k-ε model, and volume of fluid (VOF) model, shear-thinning carboxymethyl cellulose (CMC) was selected to simulate marine organisms like jellyfish. Fluent software was employed to numerically simulate the performance characteristics and internal flow field of the annular jet pumps. The results demonstrate that the shear-thinning effect of non-Newtonian fluids reduces the maximum efficiency point of annular jet pumps and decreases the flow rate ratio corresponding to this efficiency point. As the concentration of CMC solution increased to 0.5%, the maximum efficiency point decreased by 5.5%, and the flow rate ratio corresponding to this efficiency point dropped from 1 to 0.8. These findings provide reference and insights for analyzing the full flow field of annular jet pumps pumping shear-thinning non-Newtonian fluids and for structural design of such pumps.