Boundary-layer control by electric fields: A feasibility study
نویسنده
چکیده
A problem of great concern in aviation and submarine propulsion is the control of the boundary layer and, in particular, the methods to extend the laminar region as a means to decrease noise and fuel consumption. In this paper we study the flow of air along an airfoil when a layer of ionized gas and a longitudinal electric field are created in the boundary layer region. By deriving scaling solutions and more accurate numerical solutions we discuss the possibility of achieving significant boundary layer control for realistic physical parameters. Practical design formulas and criteria are obtained. We also discuss the perspectives for active control of the laminar-to-turbulent transition fluctuations by electromagnetic field modulation. 1 Boundary layers and boundary layer control Whether a flow is laminar or turbulent, the effects of the viscosity of the fluid are greatest in regions close to solid boundaries. The region close to
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