DESIGN OPTIMIZATION OF HELICOPTER BLADE USING CLASS SHAPE FUNCTION BASED GEOMETRY REPRESENTATION

摘要

In this paper, a twist distribution of thehelicopter blade is optimized to maximize thehelicopter efficiency and the influence of therequired power is investigated. A multiobjectiveoptimization problem was set tosearch optimal designs for hovering andforward flight condition. The efficiency ofhelicopter rotor blade for hovering can bemeasured by a figure of merit and for a forwardflight can be measured by the ratio betweenThrust (CT) and a summation value of in-planeH force (CH) and total torque (CQ) divided bythe advance ratio (μ). Blade element momentumtheory is deployed to evaluate the design forforward flight and hovering conditions. Thetwist distribution of helicopter blade iscontrolled by the class shape functiontransformation parameterization. The NondominatedSorting Genetic Algorithm withmulti-modal distribution crossover method wasused to solve multi-objective optimizationproblems. From results of optimization problemfound that the twist has an effect of the changein drag force that acts on the blade structure onthe figure of merit.