Bird With A Bite

摘要

One of the trends with lighter indoor foamie aircraft is to have vortex generators on the wings and other control surfaces. The new Thunder Power Razorback biplane (thunderpower-batteries.com), from a recent review in Model Airplane News, is a good example of vortex generators on the wings. Between the top and bottom wing, there are 56 of them. We had to ask ourselves, do these generators really improve the airplane's performance? For our answer, we looked at full-size aircraft and the company that manufactures the micro vortex generators. In full-size aircraft, the micro vortex generators are small, metal, trapezoid-shaped, fin-like blades placed in a spanwise line aft of the leading edge of the wing. They control airflow over the upper surface of the wing by creating vortices that energize the boundary layer. This is the way vortex generators work. As air normally flows over a plane's wing during flight, the air "clings" to the wing's surface. As long as the air clings, the wing will produce lift. If the airflow loses its adherence and detaches from the wing, the aircraft will lose lift and have increased drag.