Search results
Results from the WOW.Com Content Network
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.
The power is equal to the drag force times velocity. For aircraft in cruise flight the lift is equal to the weight (L=mg) and the engine thrust is equal to the drag (T=D). Hence, ϵ = P / ( m g v ) = D / L = 1 / f {\displaystyle \epsilon =P/(mgv)=D/L=1/f} , with f=L/D the lift-to-drag ratio , so the specific resistance of airplanes is roughly ...
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 ]
The aerodynamic force is the resultant vector from adding the lift vector, perpendicular to the flow direction, and the drag vector, parallel to the flow direction. Forces on an aerofoil . In fluid mechanics , an aerodynamic force is a force exerted on a body by the air (or other gas ) in which the body is immersed, and is due to the relative ...
What links here; Upload file; Special pages; Printable version; Page information; Get shortened URL; Download QR code
L/DMAX occurs at minimum Total Drag (e.g. Parasite plus Induced) Coefficients of Drag and Lift vs Angle of Attack. Stall speed corresponds to the Angle of Attack at the Maximum Coefficient of Lift. The lift-to-drag ratio, or L/D ratio, is the amount of lift generated by a wing or vehicle, divided by the drag it creates by moving through the air ...
The logarithmic term with weight ratios is replaced by the direct ratio between / = where is the energy per mass of the battery (e.g. 150-200 Wh/kg for Li-ion batteries), the total efficiency (typically 0.7-0.8 for batteries, motor, gearbox and propeller), / lift over drag (typically around 18), and the weight ratio / typically around 0.3.
It is also useful to show the relationship between section lift coefficient and drag coefficient. 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 ...