Abstract: In order to improve the anti-cavitation characteristics of centrifugal pumps, based on the bionics principle, the circular bionic non-smooth surface structure was arranged at the suction surface where the centrifugal pump blade was most prone to cavitation. The numerical simulation method was used to analyze the external characteristics, bubble volume, turbulent kinetic energy and pressure distribution characteristics of centrifugal pumps with different diameters of circular non-smooth surface blades under different cavitation allowances. The effects of circular non-smooth surface blades on the cavitation performance of centrifugal pumps were studied. The results show that centrifugal pumps with circular protrusion diameter of 0.5 mm and 1.0 mm have high heads and great efficiency, which are close to the values of centrifugal pumps with smooth surface blades. In severe cavitation, the centrifugal pump with circular protrusion diameter of 1.0 mm has the smallest bubble volume. The low pressure section of the impeller is small, the pressure gradient is large, and the turbulent energy near the wall surface of the suction surface of the blade is increased, with the result that the pressure drag caused by the separation is reduced, which has a good inhibitory effect on cavitation.

Key words: centrifugal pump, cavitation, non-smooth surface, numerical simulation, bubble