Viscous flow past a rotating sphere with a constant rotating speed about an axis aligned with the free stream was investigated numerically by solving the three-dimensional Navier-Stokes equations using the finite elem...Viscous flow past a rotating sphere with a constant rotating speed about an axis aligned with the free stream was investigated numerically by solving the three-dimensional Navier-Stokes equations using the finite element method. To elucidate the character of this flow in the near wake, the flow structures at different Reynolds numbers and rotating speeds are examined. The axisymmetric and non-axisymmetric flow structures were observed at Re=200 and 250, respectively, which rotate as a whole around the rotating axis steadily. At Re=300, the vortex shedding appears and the wake becomes more complicated. At low rotating speeds, the flow is dominated by the vortex shedding at higher Reynolds numbers. As the rotating speed increases, the rotating effect gets stronger and the interaction between the rotating action and the vortex shedding results a swirling vortex pattern in the near wake of the sphere.展开更多
文摘Viscous flow past a rotating sphere with a constant rotating speed about an axis aligned with the free stream was investigated numerically by solving the three-dimensional Navier-Stokes equations using the finite element method. To elucidate the character of this flow in the near wake, the flow structures at different Reynolds numbers and rotating speeds are examined. The axisymmetric and non-axisymmetric flow structures were observed at Re=200 and 250, respectively, which rotate as a whole around the rotating axis steadily. At Re=300, the vortex shedding appears and the wake becomes more complicated. At low rotating speeds, the flow is dominated by the vortex shedding at higher Reynolds numbers. As the rotating speed increases, the rotating effect gets stronger and the interaction between the rotating action and the vortex shedding results a swirling vortex pattern in the near wake of the sphere.