A cavitation performance prediction method for pumps PART1-Proposal and feasibility

Abstract

Pumps are essential machinery in the various industries. With the development of high-speed and large-scale pumps, especially high energy density, high requirements have been imposed on the vibration and noise performance of pumps, and cavitation is an important source of vibration and noise excitation in pumps, so it is necessary to improve pumps cavitation performance. The modern pump optimization design method mainly adopts parameterization and artificial intelligence coupling optimization, which requires direct correlation between geometric parameters and pump performance. The existing cavitation performance calculation method is difficult to be integrated into multi-objective automatic coupling optimization. Therefore, a fast prediction method for pump cavitation performance is urgently needed. This paper proposes a novel cavitation prediction method based on impeller pressure isosurface at single-phase media. When the cavitation occurs, the area of pressure isosurface Siso increases linearly with the NPSHa decrease. This demonstrates that with the development of cavitation, the variation law of the head with the NPSHa and the variation law of the head with the area of pressure isosurface are consistent. Therefore, the area of pressure isosurface Siso can be used to predict cavitation performance. For a certain impeller blade, since the area ratio Rs is proportional to the area of pressure isosurface Siso, the cavitation performance can be predicted by the Rs. In this paper, a new cavitation performance prediction method is proposed, and the feasibility of this method is demonstrated in combination with experiments, which will greatly accelerate the pump hydraulic optimization design.