Numerical simulation on vortex structure within a magnetic vortex pump with numerous short straight blades

Due to the operational differences between vortex pumps and traditional vane pumps, complex vortex structures exist within vortex pumps. As the fluid gains mechanical energy repeatedly, the vortex also give rise to issues such as hydraulic losses, vibration, and noise. This study conducts a numerical simulation on vortex structures within a magnetic vortex pump with 56 short-straight blades on a single side and staggered blade arrangement on both sides. The numerical simulations are validated against experimental data. Based on numerical calculations, pressure pulsations and velocity pulsations within the impeller passages and casing were analyzed. Additionally, the distribution of pressure pulsation intensity, vorticity intensity, and turbulent kinetic energy dissipation at the rotor-stator interface was investigated. Finally, the vortex structures within the impeller and casing passages, along with their effects on the flow field, were analyzed in the axial, circumferential, and radial directions. Results show the numerical predictions agree well with experimental data. Influenced by the periodic evolution of vortices, velocity pulsations in the impeller and volute do not occur solely at the blade passing frequency. Circumferentially, two counter-rotating vortices exist on either side of the impeller, inducing a significantly higher velocity at the mid-section of the impeller outlet. Additionally, the vertical velocity near the blade root at the impeller inlet is bigger than that near the blade trailing edge. A radial flow separation vortex near the blade suction side creates a substantial pressure gradient from the pressure side to the suction side.