Lift per unit span = ρ × V × Γ Where ρ is density, V is freestream velocity, and Γ is circulation.
This text argues that most introductory explanations of lift (the "equal transit time" or "venturi" theories) are physically wrong. To truly understand how air behaves around a wing, we must start with the real physics: Newton’s laws, the conservation of mass and momentum, and the nature of pressure fields. We will rebuild the concept of aerodynamic force from the ground up, using only demonstrable physics. Section 1: The Great Deception (Why your first explanation was wrong) If you have ever been told that air molecules must meet at the trailing edge because they split at the leading edge, you have been taught a lie. This "equal transit time" theory implies the air over the curved top must move faster, and via Bernoulli, that faster air creates lower pressure. It sounds neat. It is also unphysical . understanding aerodynamics arguing from the real physics pdf
Do not settle for stories that feel good. Test every explanation against Newton’s laws and the conservation of mass. If an explanation cannot account for a flat plate flying upside-down, discard it. Real aerodynamics is not magic; it is the beautiful, inevitable consequence of a solid object moving through a fluid that must obey three simple rules. Master those rules, and you master the air. Lift per unit span = ρ × V
Understanding Aerodynamics: Arguing from the Real Physics We will rebuild the concept of aerodynamic force