Flow control effects of electromagnetic force in the boundary layer
流体边界层上电磁力的控制效应研究

The controlling effects of flow caused by electromagnetic body forces have been conducted. The key parameters of control experiments have been confirmed by the theoretical analysis and the numerical simulation. The electrodes and the magnetic poles are flush mounted on the cylinder surface side by side in the order of magnet N-pole, positive(negative) electrode, magnet S-pole, negative(positive) electrode, and so on. The cylinder covered with electro-magnetic actuator is immerged in the flowing electrolyte solution. The electromagnetic body forces, which localized on the circular cylinder surface, have been used to modify the boundary layer of flow and control the flow flied structure. By means of the electro-magnetic shielding and the time-region control methods, the separation points of the circular-cylinder flow are moving between the front stay point and the back stay point as the varieties of the space-time distribution parameters of the electromagnetic forces, and it brings different control effects. The electromagnetic force modified on the boundary layer is convenient to controlling the flow flied structure of the circular-cylinder flow and the cylinder wake, and it is achieved the obvious effects of the vortex suppression and the vortex acceleration. There are provided with the preferable effects of the oscillation absorption and the drag reduce while the positive electromagnetic forces processed. There are existed very strong effects of damping control while the negative electromagnetic forces processed, at that time the characteristics of symmetry and stability of the vorticity distribution on the cylinder surface are destroyed.