Cavitation performance of high-speed centrifugal pump with annular jet and inducer at different temperatures and void fractions

The cavitation is very common in a centrifugal pump, especially when the speed is very high, and it seriously influences the centrifugal pump performance. In this investigation, the RNG k-ε turbulence model and the cavitation model with consideration of the mass transferring are first used to simulate the cavitation performance of the high-speed centrifugal pump without taking any measure for improving the pump cavitation performance. The calculation results reveal that a number of bubbles appear in the centrifugal pump flow channel, and the head as well as the flow rate of the high-speed centrifugal pump are far from its design condition. The cavitation performance can be improved effectively by arranging a variable pitch inducer and adopting an annular nozzle scheme. The flow field analysis of the pump is conducted to obtain the suitable working temperature distribution at different void fractions. On one hand, with the same void fraction, the head of the centrifugal pump drops slowly with the increase of temperature. However, when the temperature exceeds 90℃, the head of the pump drops rapidly. On the other hand, at the constant temperature, the higher the void fraction, the worse the cavitation performance. This research conducted under different temperatures and void fractions provides some guidance for designing an effective high-speed centrifugal pump.