The Research Of Electromagnetic Control In Cylinder Wake

As a part of a project "Electromagnetic control in cylinder wake and propulsion of detonation", this paper presents the numerical simulations of electromagnetic control in cylinder wake.Based on the vorticity/stream function formulation of the Navier-Stokes equations considering the electro-magnetic body force, i.e. Lorentz force, in the exponential-polar coordinates the numerical simulations on the wake of a cylinder, covered with electro-magnetic actuators, were performed. The results of distributions of vorticity and velocity, drag force and lift force were obtained.The above results were analyzed and discussed, and were compared with experimental results , the conclusions obtained are as follows:The electromagnetic body forces, which caused by the electromagnetic field and localized around on the circular cylinder surface, can be used to modify the boundary layer of flow and can control the flow flied structure of the circular-cylinder flow in electrolyte solution. Under the influence of different Lorentz force, obvious effect of vortex suppression and vortex acceleration were obtained, and the separation points of the circular-cylinder flow were moving between the front stay point and the back stay point.When Lorentz force and fluid flows were in the same direction, preferable effects of the lift suppression and the drag reduce can be obtained whereas, the characteristics of symmetry and stability of the vorticity distribution on the cylinder surface were destroyed. The control effect of electromagnetic force on cylinder wake, lift force and drag force, which was caused by alternating current, is related to its frequency.