Category archives for flying

Bluff Body Flow: Potential Flow with 3D Rotational Separation


            We show as part of the revelation of The Secret of Flight that slightly viscous bluff body flow, such as the flow around a wing, can be described as potential flow modified by 3d rotational separation with point stagnation. This makes slightly viscous bluff bod flow both computable and […]

Aerodynamics Text Book: Incorrect


The standard aerodynamics text book Aerodynamics for Engineering Students, 5th edition, by Houghton and Carpenter informs the students in Chapter 4: By the end of the 19th century the theory of potential flow was extremely well developed. But for the most important practical applications in aerodynamics potential flow was almost a complete failure. Flow separation and […]

Early Developments of Modern Aerodynamics: Incorrect!


We read in the opening chapter of Early Developments of Modern Aerodynamics by Ackroyd, Axcell and Ruban: Our stress on viscosity will no doubt surprise newcomers to the subject. However, it must be emphasized at the outset that, without viscosity, all flight, even in nature, would be impossible since wings would produce no lift. From this it follows that […]

No Effect of Rounded Trailing Edge on Drag and Lift


                  New Theory of Flight presented on The Secret of Flight  is based on an analysis of computational solutions of the Navier-Stokes equations with slip boundary condition showing that the rotational slip separation pattern at the trailing edge (shown in the picture above) has an important role for […]

New Theory of Flight


The New Theory of Flight which I have developed together with Johan Hoffman and Johan Jansson, has now been submitted to AIAA together with a supporting article about the completely crucial issue of separation in slightly viscous flow, as a further elaboration with more computational support of the articles The Mathematical Secret of Flight, NORMAT 57 (2009) […]

Why It Is Possible to Fly

The secret of gliding flight


A new explanation is presented of how a wing generates large lift with small drag, based on computing turbulent solutions to the incompressible Euler equations. It is seen that the same mechanism which generates drag from low-pressure streamwise vorticity at the trailing edge, redistributes the pressure over the wing surface and thereby generates lift. It is shown that the classical explanation by Kutta-Zhukovsky is purely fictional and does not describe real physics of gliding flight.