电磁体积力作用下的圆柱绕流实验研究

EXPERIMENTAL STUDY ON CIRCULAR-CYLINDER FLOW MODIFIED BY ELECTROMAGNETIC BODY FORCES

利用电介质溶液中圆柱体侧表面附近分布的电磁场产生电磁体积力,作用于流体边界层,从而控制圆柱绕流。电极与磁极交替分布的电磁场激活板包覆在圆柱体表面置于流动的电解质溶液中,产生的电磁力沿圆柱体表面分布,可以改变流体边界层结构。在流体边界层上电磁体积力的作用下,圆柱绕流分离点可以在前驻点和后驻点之间变动,产生不同的控制效果。调整电磁场的时空分布控制参数,电磁体积力能连续控制圆柱绕流、尾流涡街的形态,具有明显的消涡与增涡控制效应;具有较好的减震、减阻控制效果;具有制动控制效应。

The electromagnetic body forces, which is caused by the electromagnetic field and is localized on the circular cylinder surface, have been used to modify the boundary layer of flow and control the flow field of the circular-cylinder flow in electrolyte solution. The key parameters of control experiments have been confirmed by theoretical analysis and numerical simulation. The electrodes and the magnetic poles are flush mounted on the cylinder surface side by side in the sequence 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. By using the electro-magnetic shielding and the time-region control methods, the separation points of the circular-cylinder flow are moving between the front stagnation point and the back stagnation 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 in controlling the flow field structure of the circular-cylinder flow and the cylinder wake, and it achieves the obvious effects of the vortex suppression and the vortex acceleration. The method provides preferable effects of vibration suppression, drag reduction, and damping control.