Fan Component Noise Prediction And Influence Analysis During Aircraft Approach

With the fast development of civil aviation industry and constant increase of aircraft number,the aircraft noise problem has attracted people’s wide attention.Aeroengine fan is an important noise source of modern civil aircraft.Therefore,lots of research has been done on the fan noise of engine.However,the previous noise prediction on the fan or other engine components was done under static condition,and it wasn’t connected with flight status required by airworthiness regulations.So it will be more significant to predict the fan noise under the airworthiness condition.In this paper,some basic knowledge of acoustic and production mechanism of engine fan noise were introduced in the first place.And Heidmann large fan noise prediction model after being improved was also introduced.In combination with landing procedure of aircraft in airworthiness regulation of CAAC.After realistic corrections such as doppler effect correction,geometric divergence correction,correction of noise atmosphere absorption.Fan component noise prediction model during aircraft approach was constructed.The model has been realized through matlab coding.And the feasibility of the model has also been certificated by the aeroengine example during aircraft approach process.Fan component noise during approach process of another two types of aircrafts’ aeroengines were also predicted.Variations of SPL,PNL,OASPL and dBA of fan component noise during aircraft approach were analyzed.At last,influences of some atmosphere environment factors,aeroengine geometric parameters,design parameters and operation parameters to the fan component noise during aircraft approach were analyzed,which could offer the technique reference to the engine noise control and noise airworthiness validation.