Optimal Design of Compound Helicopters (3/7/2014 Hudson 208 @ 11:45AM)
Conventional helicopters are very inefficient in high speed forward flight. Research has shown that coaxial rotors and wing-rotor compounds can achieve improved high speed performance relative to conventional helicopters. Higher harmonic blade pitch control can also improve performance at high speeds, however it has only been researched within conventional helicopters. We present a method for computing the optimal rotor design and aerodynamic performance of conventional and compound helicopters using higher harmonic control. We show that for a coaxial rotor system using a propeller to supplement propulsive force, higher harmonic control reduces the total power requirements in high speed flight by 15%. Additionally, we show that the amount of fuselage drag of the vehicle has an important effect on optimal shaft angle of attack, rotor design, and propulsive force sharing, and should be carefully considered in the preliminary design of a compound helicopter.
Eli is a 3rd year PhD student at Duke. He holds a B.S. in Mechanical Engineering from the University of Virginia and an M.S. from Duke. Before returning to graduate school, Eli worked for two years as an engineer at the Knolls Atomic Power Laboratory.