Numerical Investigations on Phase Cancelation of Interaction Noise for Counter-Rotating Propellers

The large interaction tonal noise of counter-rotating propellers significantly restricts their application in civil aviation. A pair of counter-rotating propellers was simulated by the lattice Boltzmann method, and the far-field noise was predicted by the Ffowcs Williams and Hawkings analogy. Dynamic mode decomposition was introduced to analyze the surface pressure contribution to far-field noise and to provide insights on the cancellation mechanism of the noise source distribution for the interaction tone. It was found that the cancellation effect is closely related to the relative position between the front blade wake and rear blade element. By adjusting the rear blade sweep and, hence, changing the relative position, the interaction tone can be reduced effectively.