Thin Aerofoil Theory for Development of A Turbine Blade P M V Subbarao Professor Mechanical Engineering Department A Generalized Creative Mathematics…..

Airfoil Analysis The first step in airfoil design is choosing a method. A variety of computational methods are available to the airfoil designer. Linear methods -- concerned with solving the velocity potential equation Complicated methods that involve solving the Euler (inviscid) equations at various locations around a known geometry. The linear methods are much faster but much more limiting in application. Panel methods are most popular of the linear methods.

Three Basic Problems of Thin Aerofoil Theory

The thickness problem Let the thickness disturbance field be represented by a distribution of mass sources along the x -axis in the range 0 <x < C .

The Camber Problem

Forces and moments on a thin cambered airfoil at zero angle of attack

The Angle of Attack Problem

Theory Vs Truth

Role of Viscous Forces

Solution of N-S Equation : Angle of Stall

Panel methods Panel methods are numerical models based on simplifying assumptions about the physics and properties of the flow of air over an aircraft. The viscosity of air in the flow field is neglected. However, the net effect of viscosity on a wing is summarized by requiring that the flow leaves the sharp trailing edge of the wing smoothly. The compressibility of air is neglected, and the curl of the velocity field is assumed to be zero. The vector velocity describing the flow field can be represented as the gradient of a scalar velocity potential. The resulting flow is referred to as potential flow.

The Source Consider a point source