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A supercritical aerofoil (supercritical airfoil in American English) is an airfoil designed primarily to delay the onset of wave drag in the transonic speed range. Supercritical airfoils are characterized by their flattened upper surface, highly cambered ("downward-curved") aft section, and larger leading-edge radius compared with NACA 6-series ...
After World War II, NACA research began to focus on near-sonic and low-supersonic airflow.After considering the sudden drag increase which a wing-fuselage combination experiences at somewhere around 500 mph (800 km/h), Whitcomb concluded that "the disturbances and shock waves are simply a function of the longitudinal variation of the cross-sectional area" – that is, the effect of the wings ...
, is the coefficient of lift of a specific section of the airfoil, t is the airfoil thickness at a given section, c is the chord length at a given section, is a factor established through CFD analysis: K = 0.87 for conventional airfoils (6 series), [4] K = 0.95 for supercritical airfoils.
Anti-shock body is the name given by Richard T. Whitcomb to a pod positioned on the upper surface of a wing. [1] Its purpose is to reduce wave drag while travelling at transonic speeds (Mach 0.8–1.0), which includes the typical cruising range of conventional jet airliners.
The supercritical airfoil is a type that results in reasonable low speed lift like a normal airfoil, but has a profile considerably closer to that of the von Kármán ogive. All modern civil airliners use forms of supercritical aerofoil and have substantial supersonic flow over the wing upper surface.
The research suggests matter is not as “clumpy” as would be expected based on the current best model of the universe. According to the scientists, this adds to a body of evidence that there ...
Transonic (or transsonic) flow is air flowing around an object at a speed that generates regions of both subsonic and supersonic airflow around that object. [1] The exact range of speeds depends on the object's critical Mach number, but transonic flow is seen at flight speeds close to the speed of sound (343 m/s at sea level), typically between Mach 0.8 and 1.2.
English: Subsonic (1) and trans-sonic (2) airfoils at identical Mach number. A: Supersonic flow region . B: Shock wave . C: Area of stalled flow . On the trans-sonic (or supercritical) airfoil, the deceleration of the flow on the top surface, and the strength of the shockwave with which the flow returns to a subsonic regime, are reduced.