Prediction And Influence Analysis Of The Lateral Core Engine Noise

At present,the large aircraft C919 has entered the test phase,and there will be929 domestic large aircraft in the future,which indicates that the demand of domestic civil aircraft airworthiness certification will be increasing.In order to obtain the airworthiness certificate,the new aircraft must pass the noise airworthiness.According to the requirements of the CCAR36,the result of the noise airworthiness validation should be measured in many flight tests,which will take a lot of time and resources.Since the engine noise is the main source of the noise,so compared with the traditional flight test,predicting the engine noise in advance is beneficial to reduce the cost of test.The study shows that this method is feasible,and the predicted results fit the actual situation of the engine noise.Along with the rapid development of aviation technology,the high bypass ratio turbofan engine is used more and more popular in the field of civil aviation.The core engine noise proportion is increasing,so it is of great significance to study the of the turbofan core engine noise and through the analysis of noise prediction and influence to reduce the engine noise.Especially the domestic large aircraft C919 has completed its first flight and begin the airworthiness certification work,the corresponding CJ-1000 A engine of AECC CAE is also accelerating the development.The prediction of relevant noise through certain parameters during airworthiness or development is also of great benefit in reducing the test cost.This paper first reviews the relevant knowledge of jet aircraft noise airworthiness validation,and then study the generation mechanism and prediction method of combustion chamber and the high-pressure turbine noise.Based on ANOPP's SAE model and Smith & Bushell model,the prediction algorithm is transformed into flight condition,and the sideline noise of two typical turbofan core engines is predicted and verified,which realizes the prediction from static to airworthiness condition.Finally,the influence factors of the sideline noise of the core engine are studied.The influence of environmental parameters and core engine parameters on the sideline noise of coreengine is mainly considered,which may provide a reference for future turbofan engine's airworthiness certification and possible noise reduction programs.