The Boundary layer concept Ludwig Prandtl 1875 1953

The Boundary layer concept Ludwig Prandtl 1875 -1953

Application of boundary layer control § Delay separation of the boundary layer § Increase the heat transfer rate

Techniques to reduce drag § Passive § Active § Compound

Some passive techniques Vortex generator Leading edge slat

Some active techniques suction boundary layer control Mobile surface

Electro-hydrodynamic method

Corona wind

airfoil under the influence of electric field Electrical potential charge density

stream line analyze V=0 kv H=1 cm V=15 kv H=0. 1 cm

The Cylinder under the influence of electric field

Re=100 Re=40 V=0 kv V=15 kv