Search results
Results from the WOW.Com Content Network
Lift is always accompanied by a drag force, which is the component of the surface force parallel to the flow direction. Lift is mostly associated with the wings of fixed-wing aircraft , although it is more widely generated by many other streamlined bodies such as propellers , kites , helicopter rotors , racing car wings , maritime sails , wind ...
The section lift coefficient is based on two-dimensional flow over a wing of infinite span and non-varying cross-section so the lift is independent of spanwise effects and is defined in terms of ′, the lift force per unit span of the wing. The definition becomes
Kutta–Joukowski theorem relates lift to circulation much like the Magnus effect relates side force (called Magnus force) to rotation. [3] However, the circulation here is not induced by rotation of the airfoil. The fluid flow in the presence of the airfoil can be considered to be the superposition of a translational flow and a rotating flow.
The force on a rotating cylinder is an example of Kutta–Joukowski lift, [2] named after Martin Kutta and Nikolay Zhukovsky (or Joukowski), mathematicians who contributed to the knowledge of how lift is generated in a fluid flow.
Bernoulli's principle can be used to calculate the lift force on an airfoil, if the behaviour of the fluid flow in the vicinity of the foil is known. For example, if the air flowing past the top surface of an aircraft wing is moving faster than the air flowing past the bottom surface, then Bernoulli's principle implies that the pressure on the ...
Lifting line theory supposes wings that are long and thin with negligible fuselage, akin to a thin bar (the eponymous "lifting line") of span 2s driven through the fluid. . From the Kutta–Joukowski theorem, the lift L(y) on a 2-dimensional segment of the wing at distance y from the fuselage is proportional to the circulation Γ(y) about the bar a
The lift force L on a wing of area A, traveling at true airspeed v is given by =, where ρ is the density of air, and C L is the lift coefficient. The lift coefficient is a dimensionless number that depends on the wing cross-sectional profile and the angle of attack. [12]
Lift and drag are the two components of the total aerodynamic force acting on an aerofoil or aircraft.. In aerodynamics, the lift-to-drag ratio (or L/D ratio) is the lift generated by an aerodynamic body such as an aerofoil or aircraft, divided by the aerodynamic drag caused by moving through air.