O. Leon, F. Gandhi

Spanwise-segmented Trailing Edge Flaps (TEFs) were examined for rotorcraft power reduction. Four TEFs, extending from 50-60%, 60-70%, 70-80% and 80-90% span, were considered and actuated at frequencies up to 2/rev. A gradient-based optimization scheme was used to determine the optimal deployment of the TEFs that minimized rotor power, while satisfying vehicle trim. Studies were based on a UH-60 type aircraft and the effect of the TEFs was examined at moderate to very high speeds, and for low through high aircraft gross-weights. In the analysis CFD generated lift and drag increments associated with TEF deflections were added to airfoil properties of the base SC-1094R8 airfoil. At high gross-weight and airspeed, reductions in rotor power of up to nearly 8% were observed for blades with a -8 deg linear twist, and up to 5.65% when the nonlinear twist of the UH-60 was used. The power reduction was predominantly due to a reduction in profile power, especially at the higher gross weights and advance ratios. In general, the TEFs moved lift inboard and offloaded the tip regions. Even though the drag increased slightly inboard, the large reduction in drag along the outer rim, along with the large moment arm, reduced rotor torque and power.

35th European Rotorcraft Forum 2009,

Conference Paper

englisch

21,0 x 29,7 cm, 15 Seiten

DGLR-Bericht, 2009, 2009-03, 35th European Rotorcraft Forum 2009 - Conference Proceedings; S.1-15; 2009; Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V., Bonn

NA

in getr. Zählung;

flaps (control surfaces), rotors, trailing edges, rotorcrafts

Bestellbar

2009