Abstract: To address excessive energy dissipation and flow instability caused by tip-leakage flow (TLF) in centrifugal pumps, this study designs two bio-inspired triangular grooved tip structures (Bio-seg, Bio-con) based on the shell surface features of Chlamys farreri and Argopecten irradians. The SST k-ω turbulence model combined with entropy generation theory was adopted for steady and unsteady full-flow field numerical simulations of a centrifugal pump conveying shear-thinning EVA latex, with the numerical model validated comprehensively by experiments. Results demonstrate that the Bio-seg structure enables momentum exchange between TLF and trapped fluid via its segmented grooves, weakening the interaction intensity between TLF and the main flow. This thus reduces the entropy generation losses in the impeller and volute by 35.6% and 15.1% respectively (with an overall reduction of 20.2%), and lowers the pressure pulsation amplitudes at the dominant frequency by 29.1% (impeller) and 9.6% (volute) respectively. It also boosts pump head and efficiency by 2.5% and 2.7% versus the original impeller. In contrast, Bio-con exhibits limited effects (3.7% total entropy reduction, 1.0% head and 1.2% efficiency gains) due to the vortex effect in continuous grooves weakening TLF blocking efficiency. This work proposes a novel bio-inspired topological design method for energy loss and pressure pulsation control in centrifugal chemical pumps, providing a structural optimization solution for their efficient and stable operation.

Key words: Centrifugal pump')">Centrifugal pump, Tip-leakage flow, Bionic structure, Entropy generation theory