Roots Fan Sound Insulation Device Based On Film-type Acoustic Metamaterial Research And Application

With the rapid development of social economy and science and technology,people's quality of life is getting higher and higher.While enjoying the convenience brought by modern civilization,human beings have put forward higher requirements on the social environment.People always hope to be able to Working and living in a quiet and peaceful environment,and the existence of the Roots blower seems to declare the destruction of this hope,because the Roots blower is a well-known "sound tiger" in the industry.Noise has a serious impact on people's physiology and psychology.The continuous effect of strong noise can make people's hearing decline,and when severe,it leads to permanent hearing loss.Over time,it will produce noise deafness;long-term work in high-noise environments is easy Suffering from neurasthenia,vision loss,high blood pressure and other diseases,makes people nervous,irritable,anger and other emotions,work efficiency is reduced,the error rate is increased,and sometimes even disaster accidents are caused,which is extremely harmful to human health and life safety Threat.The Roots blower is widely used in industries such as sewage treatment,biopharmaceuticals,textile printing and dyeing,food and paper making due to its simple structure,convenient manufacturing,high wind pressure and large air volume.This article takes the ZLS-32 L Roots blower as the research object,applies the latest research results of the film-type acoustic metamaterial to the sound insulation device,blocks the fan noise propagation path,and uses a combination of simulation and experiment to reduce the sound insulation cover.Research and design of noise and heat dissipation performance.The main research contents of this article are as follows:(1)In this paper,the four-point measurement free sound field method is used to measure the radiated noise of the Roots blower,the noise measurement site is checked,the background noise and the overall noise of the fan are measured,and each frequency band of the ZLS-32 L Roots blower is obtained by noise spectrum analysis Determine the noise reduction target amount,and take the frequency at the noise peak as the noise reduction target frequency point.If the noise value at this frequency point can be reduced,the overall noise of the fan will also be controlled.(2)The film-type acoustic metamaterial is composed of three parts: supporting frame,additional mass,and elastic film.In this paper,the film-type acoustic metamaterial is used in the sound insulation device of the Roots blower.The LMS Virtual Lab acoustic software is used to compare the material and structure.The sound insulation performance of film-type acoustic metamaterials is studied.In terms of materials: the base material of the sound insulation cover,additional weight materials,and elastic film materials;in terms of structure:the shape of the weight,the size of the weight,the length of the sound insulation unit,and the distance from the elastic film to the surface of the substrate Through the simulation analysis of these parameters,the composition of the film-type acoustic metamaterial is determined.(3)The Roots blower is a heat-generating device.If it is completely enclosed in a sound insulation hood,it is likely to damage the mechanical equipment because the temperature in the hood is too high.Under the premise of satisfying noise control,combined with relevant design standards,a heat dissipation and ventilation window is opened for the sound insulation cover,and the required ventilation amount is calculated according to the heat production amount.If natural ventilation cannot meet the requirements,consider adding a temperature-controlled exhaust fan.(4)According to the structural characteristics of the Roots blower,determine the shape and size of the sound insulation cover,make the sound insulation cover and conduct the noise measurement experiment,fix the prepared film-type acoustic metamaterial on the inner surface of the sound insulation cover,and conduct the noise measurement experiment again.Through the comparison of the two experimental data,the sound insulation performance of the film-type acoustic metamaterial was evaluated.The ambient temperature in the hood conformed to the operating conditions of the Roots blower.