输送廊道悬浮声屏障插入损失计算模型

为准确评估输送廊道各类悬浮声屏障插入损失,并提高其计算效率,通过声衍射基础公式,考虑实际廊道输送带下方衍射现象,推导出基于线声源的有限长及无限长悬浮声屏障插入损失简化计算公式,进而提出一种考虑下衍射的输送廊道声屏障插入损失计算模型,研究了输送廊道声屏障各类型的选择与居民区所处位置之间的关系。结果表明：下挑檐和上下挑檐声屏障较单侧声屏障和上挑檐声屏障降噪效果高3-5dB。上下挑檐声屏障较下挑檐声屏障降噪效果高约1dB,声屏障高度增加(6m以内)下挑檐插入损失增长速率更快；随着声屏障距地高度增加,近场(50m)插入损失下降速率更快需要搭配其他的降噪措施,远场插入损失下降范围0.5dB内。其研究成果应用于某发电厂厂区外输送廊道噪声控制,采用下挑檐声屏障,理论计算与实际测试误差为2dB以内,达到预期效果。可见对输送廊道噪声的声屏障治理提供科学依据,具有较大的应用价值。

Research on calculation model and control method of insertion loss of sound barrier in conveying corridor

In order to accurately evaluate the insertion loss of various types of suspended sound barriers in conveying corridors and improve their calculation efficiency, a simplified calculation formula for insertion loss of finite-length and infinite-length suspended sound barriers based on line sound sources is derived by considering the diffraction phenomenon below the actual corridor conveyor belt through the basic formula of sound diffraction, and then a calculation model for insertion loss of sound barriers in conveying corridors considering under diffraction is proposed, and the relationship between the various types of sound barriers in conveying corridors The relationship between the selection of each type of conveyance corridor sound barrier and the location of the residential area is investigated. The results show that the noise reduction effect of lower and upper eaves barriers is 3-5 dB higher than that of single side barriers and upper eaves barriers, the noise reduction effect of upper and lower eaves barriers is about 1 dB higher than that of lower eaves barriers, the insertion loss of lower eaves barriers grows faster when the height of the barriers increases (within 6 m), the insertion loss of near field (50 m) decreases faster with the increase of the height of the barriers from the ground, and other noise reduction measures are needed. The insertion loss in the far field decreases within 0.5dB. The research results are applied to the noise control of the conveying corridor outside a power plant, and the error between the theoretical calculation and the actual test is within 2dB, which achieves the expected effect. It can be seen that it is of great application value to provide scientific basis for the sound barrier treatment of the noise of the conveying corridor.