The optimal design of a compound helicopter comprised of counterrotating coaxial rotors, a propeller, and optionally a fixed wing is investigated. The blade geometry, azimuthal blade pitch inputs, optimal shaft angle (rotor angle of attack), and division of propulsive and lifting forces among the components that minimize the total power for a given flight condition are determined. The optimal design problem is cast as a variational statement that minimizes the sum of induced and viscous power losses for a prescribed lift, propulsive force, and vehicle trim condition. The rotor, propeller, and wing geometry and control inputs are related to the far-field circulation through a lifting-line model that accounts for experimentally or computationally determined nonlinear lift and drag polars. The variational statement is discretized using a vortex lattice wake, and the resulting nonlinear constrained optimization problem is solved via Newton iteration. Results show that varying the prescribed propulsive force of the system affects the optimal shaft angle and rotor design, that higher harmonic control reduces the total vehicle power loss (inefficiency) in high-speed flight by as much as 15%, and that imposing a maximum allowable lateral lift offset can greatly increase the power loss of the coaxial rotors. Presented at the AHS International 70th Annual Forum & Technology Display, Montréal, Québec, Canada, 20-22 May 2014


    Access

    Access via TIB

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Optimum Design of Compound Helicopters that Use Higher Harmonic Control


    Contributors:

    Published in:

    Publication date :

    2015




    Type of media :

    Article (Journal)


    Type of material :

    Print


    Language :

    English



    Classification :

    BKL:    55.50 Luftfahrzeugtechnik / 55.50
    Local classification TIB:    770/7040



    Optimum Design of Compound Helicopters that Use Higher Harmonic Control

    Giovanetti, Eli B. / Hall, Kenneth C. | AIAA | 2015


    Optimum Design of Compound Helicopters Using Higher Harmonic Control

    Giovanetti, E. / Hall, K. / American Helicopter Society | British Library Conference Proceedings | 2014


    ICAS2014_0089: OPTIMUM AND DESIGN TRENDS OF COMPOUND HELICOPTERS

    Rand, O. / Khromov, V. | British Library Conference Proceedings | 2014


    MINIMUM POWER REQUIREMENTS AND OPTIMAL ROTOR DESIGN FOR CONVENTIONAL AND COMPOUND HELICOPTERS USING HIGHER HARMONIC CONTROL

    Hall, K.C. / Giovanetti, E.B. / American Helicopter Society | British Library Conference Proceedings | 2013