CIRA Aeroacoustic effort within the IMT project Rotorcraft Aerodynamics and Aeroacoustics (HELISHAPE)

This document summarizes the results of CIRA effort in computational task of HELISHAPE, a reserach project supported by the European Community within the framework on the IMT (Brite/Euram) programme. The main outcome is a computer program fro the prediction of noise produced by helicopter rotors. The code, named HERNOP-2 (HElicopter ROtor Noise Prediction), conceived within the HELINOISE European programme, is based on the solution of the Ffowcs Williams-Hawkings equation in time domain. Two different resolution schemes have been implemented to achieve the numerical prediction of both linear and nonlinear terms of the governing equation; the adopted solving forms enable the estimation of noise from an open, isolated rotor blade, as well as from a high speed propeller.