Identification And Reducing On The Noise Source Of A Cleaning Sweeper Truck

With the rapid development of economic technology and industrial manufacturing,new machinery is gradually being applied to all areas,which greatly facilitates the lives of people.In terms of urban road cleanliness,the sanitation special vehicles should be mentioned.Among them,the cleaning vehicle has the disadvantages of serious noise pollution while possessing the advantages of efficient cleaning.In order to solve the problem of this vehicle,a solution was proposed from the aspects of noise measurement,sound source identification and noise reduction.For the measurement of noise sources in the vehicle,the near-field measurement method was used in this paper.The LMS front end of Siemens and its associated sensors and software were used to measure the noise or vibration of the near-field points and evaluation points under different working conditions of the vehicle.The signal was measured and the information required for sound source identification was obtained.In the aspect of noise source identification,this paper first uses the spectrum analysis method to locate the noise source with simple frequency,and based on the analysis results,the adaptive network based fuzzy inference system(ANFIS)in the field of control engineering was applied to reason the complex noise source,and the reasoning results were verified with spectrum analysis.Through the combination of the two parts of the work,the final ranking of the energy contribution of each noise sources were obtained,in which the fan accounted for the largest proportion.In terms of fan noise reduction,this paper based on the joint simulation method of Fluent and Virtual.Lab,combined with response surface methodology,designed and optimized a multistage compound muffler for fan in comprehensive consideration of the amount of muffler,loss of fan performance and the strength of muffler.The muffler theoretically has certain noise reduction.Through the process of the tests,identifying and reduction of noise,not only do the noise level of the entire vehicle has been reduced,but also a set of sound source identification scheme based on the ANFIS has been proposed.The identification method can provide reference for vehicle noise identification of other similar special vehicles;in the muffler design,it provides a fan muffler design scheme that considers multiple factors.