Predicting the Influence of Blade Shape on Hover Performance with Comprehensive Analyses

Abstract

The ability to predict and understand the influence of rotor tip shape on hovering rotor performance is critical to rotorcraft development. Comprehensive rotorcraft analysis methods are an efficient way to reduce the risk and cost associated with developing new rotor designs. In the modern design environment, these methods are ideal for efficiently traversing the design space in order to identify designs of interest suitable for more detailed analysis, testing, and optimization. In this paper, the ability of three distinctly different comprehensive rotorcraft methods (EHPIC, CHARM, and VTM) to predict the hover performance of a rotor with a variety of tip shapes is evaluated. The assessment indicates that good predictive fidelity is achieved for the cases considered, though dependence on airfoil data remains a limiting factor in the generality of the analysis results.