Practical considerations in rotor design optimisation studies

Abstract

The present study demonstrates the application of an adjoint harmonic balance optimisation framework applied to the AH-64A blade. This framework allows for efficient optimisation of unsteady rotor flows whilst maintaining the fidelity of the Navier-Stokes equations. An analysis of the optimised rotor blade is presented, including the key design features that contribute to the performance benefits in each of the examined design conditions. The computational methodology and optimisation setup are analysed based on the impact on the final planform shape. The main areas of investigation include the interac tion between the treatment of rotor solidity and trim state, and the employed parameterisation process as well as the impact of solution fidelity on the optimal shape. The employed methodology leads to significant performance benefits, however, the present analysis shows that there is potential for further improvements