Flows of Air Bubbles and Solid Particles Entrained in a Mixed-Flow Pump

抄録

If air bubbles or solid particles are entrained in a pump, they will cause poor pump performance and erode the pump itself. This paper concerns theoretical estimations of three-dimensional movements of air bubbles and solid particles entrained in a mixed-flow pump. The particle movements were numerically determined by integrating the equations of motion of an air bubble or a solid particle on a water flow field, which were solved by a finite element method under assumptions of potential flow. Although the air bubbles substantially follow the water streamlines, their trajectories near the pressure surface of the impeller blades shift considerably towards the hub. The solid particles tend to move straight ahead irrespective of water streamline curvature, and they collide with the hub surface.