Author(s): Zhe Wang, Renfang Huang, Xianwu Luo, Jiajian Zhou, Lin Wang
Linked Author(s): Zhe Wang
Keywords: Axial pump, cavitating flow, Filter-Based Density Corrected Model (FBDCM)
Abstract: The present paper mainly treats the cavitating turbulent flows in a low specific speed axial pump, which is designed to be operated under the following conditions: flow discharge of 0. 56m3/s and head rise of 11m at the rotational speed of 1400r/min. In order to include the effects of vapor-water mixture on turbulent flow development, a Filter-Based Density Corrected Model, i. e. FBDCM is applied to correctly evaluate the turbulent eddy viscosity. Three-dimensional cavitating turbulent flows in the full flow passage of the pump are conducted based on a homogeneous cavitation model. For the purpose of improving the numerical accuracy, the structural grids are generated for the entire computation domain, and the clearance zone between the impeller tip and pump casing is refined as the mesh treatment near the flow walls. It is noted that hydraulic performance and cavitation performance near the design operation condition are predicted with acceptable accuracy compared with the experimental data. The internal flows show that there are strong tip leakage cavitation and sheet cavitation in the pump rotor. As the interaction of sheet cavitation and tip leakage flow, there is perpendicular cavitation in the main flow passage of the blade-to-blade channel. The better understanding of cavitating turbulent flow features in the axial pump will be helpful for further optimization to improve the hydraulic performance as well as the cavitation performance for the pump in the future
Year: 2017