A typical lift coefficient curve. The lift coefficient (CL or CZ) is non-dimensional coefficient that relates the lift generated by an airfoil, the dynamic pressure of the fluid flow around the airfoil, and the planform area of the airfoil. It may also be described as the ratio of lift pressure to dynamic pressure.
The lift force, or simply lift, is a mechanical force, generated by a solid object as it moves through a fluid, directed perpendicular to the flow direction. ...
For the kite, see foil kite. ...
Velocity pressure is also called fluid dynamic pressure or Q given by the equation. ...
A planform or plan view is a vertical orthographic projection of an object on a horizontal plane, like a map. ...
- Lift coefficient may be used to relate the total lift generated by an aircraft to the total area of the wing of the aircraft. In this application it is called the aircraft lift coefficient CL.
The lift coefficient CL is equal to:
The lift force, or simply lift, is a mechanical force, generated by a solid object as it moves through a fluid, directed perpendicular to the flow direction. ...
where L is the lift force, ρ is fluid density, v is true airspeed, q is dynamic pressure, and A is area. The lift force, or simply lift, is a mechanical force, generated by a solid object as it moves through a fluid, directed perpendicular to the flow direction. ...
For other uses, see Density (disambiguation). ...
True airspeed (TAS) is the speed of an aircraft relative to the airmass in which it flies, i. ...
Velocity pressure is also called fluid dynamic pressure or Q given by the equation. ...
- Lift coefficent may also be used as a characteristic of a particular shape (or cross-section) of an airfoil. In this application it is called the section lift coefficient cL. It is common to show, for a particular airfoil section, the relationship between lift coefficient and angle of attack. It is also useful to show the relationship between lift coefficient and drag coefficient.
The section lift coefficient is based on the concept of an infinite wing of non-varying cross-section. It is not practical to define the section lift coefficient in terms of total lift and total area because they are infinitely large. Rather, the lift is defined per unit span of the wing (L'). In such a situation, the above formula becomes:
For the kite, see foil kite. ...
In this diagram, the black arrow represents the direction of the wind. ...
The drag coefficient (Cd, Cx or Cw, depending on the country) is a dimensionless quantity that describes a characteristic amount of aerodynamic drag caused by fluid flow, used in the drag equation. ...
where c is the chord length of the airfoil. Cross section of an airfoil showing chord In reference to aircraft, chord refers to the distance between the front and back of a wing, measured in the direction of the normal airflow. ...
Note that the lift equation does not include terms for angle of attack — that is because there is no mathematical relationship between lift and angle of attack. (In contrast, there is a straight-line relationship between lift and dynamic pressure; and between lift and area.) The relationship between the lift coefficient and angle of attack is complex and can only be determined by experimentation or complex analysis. See the accompanying graph. The graph for section lift coefficient vs. angle of attack follows the same general shape for all airfoils, but the particular numbers will vary. The graph shows an almost linear increase in lift coefficient with increasing angle of attack, up to a maximum point, after which the lift coefficient falls away rapidly. This indicates the lift coefficient at the stall of the airfoil. In this diagram, the black arrow represents the direction of the wind. ...
The lift force, or simply lift, is a mechanical force, generated by a solid object as it moves through a fluid, directed perpendicular to the flow direction. ...
In this diagram, the black arrow represents the direction of the wind. ...
For the kite, see foil kite. ...
In this diagram, the black arrow represents the direction of the wind. ...
In aerodynamics, a stall is a condition in which an excessive angle of attack causes loss of lift due to disruption of airflow. ...
The lift coefficient is a dimensionless number. In dimensional analysis, a dimensionless number (or more precisely, a number with the dimensions of 1) is a pure number without any physical units. ...
Note that in the graph here, there is still a small but positive lift coefficient with angles of attack less than zero. This is true of any airfoil with camber (asymmetrical airfoils). The pressures on the upper surface of the airfoil are lower than on the bottom surface, even at zero angle of attack. The camber in aerospace engineering is the asymmetry between the top and the bottom curves of an airfoil. ...
See also
The drag coefficient (Cd, Cx or Cw, depending on the country) is a dimensionless quantity that describes a characteristic amount of aerodynamic drag caused by fluid flow, used in the drag equation. ...
The pitching moment of an airfoil, in aerodynamics, is a moment produced by a vertical force applied at a distance forward or aft from the aerodynamic center of the airfoil, causing the aircraft to pitch up or down[1]. References ↑ Preston, Ray (2006). ...
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