Analysis Of Noise Characteristics In Electric Propeller Aircraft Cabin

With the rapid development of general aviation industry,small general aircraft plays an important role in serving people's livelihood.Propeller plane is widely used because of its good economy.However,due to its own design problems,propeller aircraft have the problem of generally large vibration and noise,which will have a great impact on the comfort of aircraft.Cabin noise is an important factor affecting the comfort of aircraft.At the same time,excessive cabin noise will lead to structural safety problems and threaten the safety of passengers,which should be strictly limited.Therefore,how to control and optimize the noise of propeller aircraft cabin is of great significance.This paper adopts the electric new energy propeller aircraft cabin as the research object.Starting from the principle of noise generation in the cabin,it analyzes the noise source and sound source characteristics in the cabin,and further analyzes the noise characteristics in the cabin of the electric propeller aircraft.The cabin noise of electric propeller aircraft is simulated numerically and studied experimentally,and the cabin noise is optimized by passive noise reduction method.It is designed to reduce cabin noise and improve the comfort of the plane.In this paper,the sound field generated by propeller is numerically calculated by combining finite element method and boundary element method,so as to simulate the influence of propeller on the noise of the whole machine.The method that the aerodynamic noise generated by the propeller is equivalent to the fan sound source is selected to deal with the noise source.The sound field generated by the propeller is introduced into the acoustic simulation software Virtual Lab as an acoustic pressure excitation for calculation,and then the cabin noise response is calculated based on the acoustic vibration coupled mode to obtain the noise distribution characteristics in the cabin of the propeller aircraft.Then the contribution of noise plate in propeller aircraft cabin is analyzed and the sound pressure caused by each cabin board is calculated.Cabin noise test study,through the test,the cabin noise frequency domain characteristics and the distribution of sound pressure intensity at different rotating speeds were obtained.The experimental data and numerical calculation results of sound pressure level at different speed of propeller are compared and analyzed,and the accuracy of the numerical simulation method is proved.According to the calculation model and method established on this basis,a noise reduction method of applying noise reduction material is proposed on the premise of guaranteeing the dynamic performance of the aircraft,and the application position of noise reduction material is selected according to the plate contribution.The sound pressure level distribution of the noise in the cabin at different rotating speed is predicted.The effects of noise reduction materials on the noise in the cabin of propeller aircraft are obtained.