Numerical Investigation on internal flow characteristics of a mixed-flow pump with Tandem malposed blades

Abstract

Mixed-flow pump plays an important role in national major projects and national economic construction. In this paper, a mixed-flow pump is taken as the research object, and the internal flow characteristics and the distribution of turbulent kinetic energy in the pump under different malposed angles of blade are studied by using numerical simulation and blade modification method. The results show that the pump efficiency and head are higher when the tandem blade angles (α) are 15° and 45°, and the pump head is the largest at the α =15°, increasing by 4.37%. Meanwhile, the high-pressure area inside the impeller was large, which had a higher pressurization performance. Under the rated flow condition, the velocity curve of α =15° changes most gently, which is close to the prototype velocity curve, and the single hump zone is not obvious. The tandem malposed blades can restrain the velocity fluctuation and improve the flow field in the impeller. At α =45°, the turbulent kinetic energy dissipation and the velocity fluctuation were the smallest; the flow field was the most stable. The research results have reference significance for the optimal design and selection of mixed flow pump.