Abstract:
Abstract A comprehensive computational model, coupling the rotor CFD method based on unstructured mesh and the acoustic methods based on FW-H and Kirchhoff equations, is established to calculate the thickness, loading noise and bladevortex interaction noise as well as the transonic HSI noise of helicopter rotor. In order to improve the calculation accuracy of aerodynamic loading on blade surface, the N-S equations are used to solve the flowfield around the rotor, and the unstructured grid is employed to model blade shape well. The thickness and loading noise of rotors are calculated based on the FW-H method, and the high speed impulsive noise including quadrupole term is calculatedbased on the Kirchhoff method at the same time. By this method developed, the acoustic calculations are performed for the AH1 rotor at different flight conditions, and the good correlations with available measured data demonstrate the validation of this method. Then, the influence of the two noise prediction methods on calculated results are emphatically investigated, and the characteristics of the thickness, loading and quadrupole noise are also analyzed.