Cavitating flow features in a water-jet pump under different upstream conditions

Renfang Huang (1) , An Yu (1) , Bin Ji (2) , Jiajian Zhou (2) , Zhihong Zhai (3) , Xianwu Luo (1)

1 THU - Tsinghua University [Beijing]
2 Wuhan University [China]
3 MARIC - Marine Design and Research Institute of China [Shangai]

Turbulent cavitating flows in a water-jet mixed-flow pump were investigated by using the k-ω SST turbulence model and a cavitation model based on mass transport equation to give an insight into cavitating features under different upstream conditions. Both the hydraulic and cavitation characteristics predicted by the present numerical method agree well with the available experimental results. The numerical results depict that the cavity in the pump firstly occurs at the blade leading edge close to blade tip, and then grows both downstream and toward the impeller hub. With cavitation development, sheet cavities expand along the impeller shroud, and are likely to block the flow passage under the critical cavitation condition. Besides, the thrust of the water-jet pump is enhanced gradually during cavitation evolution, but the hydraulic performance of the diffuser remains unchanged. The hydraulic loss at the impeller suction surface increases with secondary flows and Boundary Vorticity Flux (BVF) peak during cavitation, which is located at the vapor-liquid interface, especially near the blade tip.

Mots clés: cavitating flow; water-jet pump; mixed-flow pump; numerical simulation

Domaines: Mécanique [physics]

Renfang Huang, An Yu, Bin Ji, Jiajian Zhou, Zhihong Zhai, et al.. Cavitating flow features in a water-jet pump under different upstream conditions. 16th International Symposium on Transport Phenomena and Dynamics of Rotating Machinery, Apr 2016, Honolulu, United States. ⟨hal-01894417⟩