| In recent years,the conveyor corridor has served as the main channel for the transportation of industrial raw materials,the conveying distance and frequency of use are gradually increasing,the conveyor corridor noise has different degrees of impact on residents along the route,installing sound barriers is a noise reduction measure with high efficiency and easy installation for conveying corridor noise management,but because the overhang at the bottom of the conveyor corridor sound barrier,sound propagation paths are more complex,Therefore,the accurate prediction and control of noise from suspended sound barriers in conveyor corridors are studied,and it is of great practical significance to better improve the residential sound environment of residents around the conveyance corridor.Taking the conveyor corridor as the research object,this paper studies the calculation me thod of the insertion loss of the suspended sound barrier,improves the calculation efficiency,and grasps the changing trend of the noise reduction performance of the suspended sound barr ier.After that,the equivalent noise prediction model of the suspended sound barrier is establis hed using engineering noise prediction software,which provides a more accurate modeling m ethod for the engineering noise prediction of the subsequent conveyor corridor.The main wor k contents are as follows:(1)A method for calculating the insertion loss of suspended acoustic barrier in the convey or corridor considering diffraction is proposed.In order to verify the accuracy of the calculati on method,the insertion loss of the suspended acoustic barrier is calculated through the bound ary element method.The calculation results of the two are basically consistent,which proves t hat this method can evaluate the insertion loss of the suspended sound barrier of the conveyor corridor and improve its calculation efficiency.(2)The relationship between the settings of the four types of conveyance corridor sound barriers,the settings of each parameter and the location of the residential area was analyzed.The results show that: the noise reduction effect of lower eaves and upper-lower eaves sound barriers is 3-5d B higher than that of single side sound barriers and upper eaves sound barriers,and the noise reduction effect of upper-lower eaves sound barriers is about 1d B higher than that of lower eaves sound barriers;the insertion loss growth rate of lower eaves is faster when the height of sound barriers increases;the insertion loss of near field decreases faster when the height of sound barriers from the ground increases,and the insertion loss of far field decreases within 0.5d B,and the noise reduction effect of increasing the height of sound barriers,The noise reduction effect of increasing the height of sound barrier is not obvious.(3)At the same time,the problem of insufficient noise prediction of suspended sound barrier projects and the inability to comprehensively evaluate the treatment effect of each common type of suspended sound barrier in the noise control scheme of the conveyance corridor is addressed.Based on the geometric modeling of Cadna/A noise prediction software,the geometric position relationship is used to transform the lower eave diffraction of the sound barrier into the computable upper eave diffraction,and then the equivalent noise prediction model is established and calculated,and the feasibility of the method is verified by theoretical calculation,which provides an effective way for the engineering noise prediction software to accurately predict the noise reduction effect of suspended sound barriers.(4)Apply the above two methods to noise management of power plant conveying corridors,propose three noise control schemes for simulation and calculation,compare and analyze each control scheme,and conduct field tests to provide scientific basis for noise management of the same type of corridors,which has greater application value.Figure 43 Table 13 Reference 82... |
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