FEASABILITY STUDY FOR THE PRODUCTION OF ENERGY FOR BOUNDARY LAYER SUCTION IN SOARING

Abstract

In order to achieve high cruising speeds with a high performance sailplane the altitude gained in strong up currents must be applied by means of high gliding speeds. The x'climbing or the energy growth rates in the upcurrents are often very different during one flight. The sometimes less strong climbing ranges of 5 to 20% of the overall climbing time can be used for power absorption by dispensing with further climbing in order to draw energy from the flow by means of a folding turbine. The energy stored is then used later during gliding for boundary layer suction. As a result of the boundary layer suction of the wing and tail surfaces the overall drag nearly is halved, resulting in nearly doubling the glide ratio. Decisive is the overall efficiency of the turbine, storage and suction. The storage of energy in a fly-wheel accumulator best meets this requirement. If the energy is, on the other hand, stored electrically, this offers many advantages for suction and control. The best solution is a combination of a generator and an electrical driven fly-wheel accumulator.