A digital analysis method and system for rotorcraft noise

Abstract

The invention discloses a noise digital analysis method and system of a rotorcraft. The method comprises: performing rotor flow field simulation on the rotorcraft; dividing the blades of the rotorcraft into blocks; calculating the time-domain noise of each blade block by using the FW-H equation; calculating the noise of the blade block based on the time-domain noise of the blade block Sound pressure level and noise contribution, and determine the sound source area; perform adaptive block segmentation based on pressure gradient for the sound source area; use the FW-H equation to calculate the temporal noise of each adaptive block; calculate temporal noise based on the adaptive block The sound pressure level and noise contribution of the adaptive block, and determine the location of the sound source; the digital aerodynamic noise of each adaptive block is calculated by using the noise change equation of the blade block in the complex flow area determined by the FW-H equation, and the sound is determined by the digital aerodynamic noise The cause of the noise at the source location. The invention can accurately describe the influence of the flow and the detail change of the noise, and improve the accuracy of the noise analysis of the rotorcraft.

Description

A method and system for digital analysis of rotorcraft noise technical field The present invention relates to aircraft noise analysis field, particularly relate to a kind of rotorcraft noise digital analysis method. laws and systems. Background technique [0002] The rotorcraft has a unique vertical take-off and landing mode and the ability to hover in the air, some new configuration rotorcraft, Such as tilt-rotor aircraft, high-speed coaxial helicopters, and have a certain high-speed cruise capability, which plays an indispensable role in various fields. ability. During the working process of the rotorcraft, the rotors, tail rotors and large-sized fuselage of the high-speed rotor will affect the surrounding air. The air is turbulent, resulting in aerodynamic noise. The new configuration of the rotorcraft has the characteristics of multi-rotor, multi-sound source coupling, etc. The aerodynamic environment during flight is more complex, and the influence of aerodyna...

AI Technical Summary

Problems solved by technology

[0006] To sum up, scholars at home and abroad have conducted research on rotor aerodynamic noise in various fields, and have drawn meaningful conclusions, but most of them are from the perspective of integration, considering the noise influence of the entire rotor, and it is difficult to consider the rotor flow field. The influence and internal mechanism of some details in the characteristics of the aerodynamic load and aerodynamic noise, therefore, the accuracy of the noise analysis of the rotorcraft needs to be improved

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