A simplified semi-analytical model aiming to predict the noise emitted by the main rotor of a helicopter with emphasis on the loading noise due to blade-vortex interaction is presented in this paper. The goal of this model is to be used together with the flight mechanics code EU-ROPA and should consequently have the same level of modelling. Each step of development is detailed and compared with the state of art ONERA comprehensive code HMMAP. It arises that main discrepancies are due to the wake geometry prediction, when a prescribed wake is used instead of a free wake code. On the contrary, the use of analytical response function provides rather good results by comparison with the singularity method implemented in HMMAP. This paper also demonstrates that a good acoustic prediction can not be achieved without a good rotor thrust evaluation. Nevertheless, it is found that satisfactory results, that could be used for preliminary studies, can be obtained with such a fast and simplified model.
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