Search results
Results from the WOW.Com Content Network
The drag curve or drag polar is the relationship between the drag on an aircraft and other variables, such as lift, the coefficient of lift, angle-of-attack or speed. It may be described by an equation or displayed as a graph (sometimes called a "polar plot"). [1] Drag may be expressed as actual drag or the coefficient of drag.
Graphs of C L and C D vs. speed are referred to as drag curves. Speed is shown increasing from left to right. Speed is shown increasing from left to right. The lift/drag ratio is given by the slope from the origin to some point on the curve and so the maximum L/D ratio does not occur at the point of least drag coefficient, the leftmost point.
Drag coefficients in fluids with Reynolds number approximately 10 4 [1] [2] Shapes are depicted with the same projected frontal area. In fluid dynamics, the drag coefficient (commonly denoted as: , or ) is a dimensionless quantity that is used to quantify the drag or resistance of an object in a fluid environment, such as air or water.
Induced drag must be added to the parasitic drag to find the total drag. Since induced drag is inversely proportional to the square of the airspeed (at a given lift) whereas parasitic drag is proportional to the square of the airspeed, the combined overall drag curve shows a minimum at some airspeed - the minimum drag speed (V MD). An aircraft ...
English: Drag curves for an aircraft with a given weight in flight. The parasitic drag increases with the square of flight velocity; The lift-induced drag decreases with the square of velocity. As a result, the total drag (the sum of both components) typically has a minimum value.
Drag curve for a lifting body in steady flight. Parasitic drag, also known as profile drag, [1]: 254 [2]: 256 is a type of aerodynamic drag that acts on any object when the object is moving through a fluid. Parasitic drag is defined as the combination of form drag and skin friction drag. [3] [1]: 641–642 [4]: 19
This increase can cause the drag coefficient to rise to more than ten times its low-speed value. The value of the drag-divergence Mach number is typically greater than 0.6; therefore it is a transonic effect. The drag-divergence Mach number is usually close to, and always greater than, the critical Mach number.
This allowed Galileo to show that a bullet's trajectory was a curve. [13] [9] Circa 1665, Sir Isaac Newton derived the law of air resistance. Newton's experiments on drag were through air and fluids. He showed that drag on shot increases proportionately with the density of the air (or the fluid), cross sectional area, and the square of the ...