城市轨道交通通风空调消声降噪设计要点分析

Analysis of the Main Points in Noise Reduction Design for HVAC in Urban Rail Transit

城市轨道交通的通风空调工程对环境影响评价的主要内容是风亭、冷却塔等对声环境和空气质量的影响。工程设计中应注意准确理解相关名词概念。《地铁设计规范》中明确的噪声防护距离是以常规设备为前提的,但必要时可采用低噪声设备或降噪措施来满足要求。在城市轨道交通环境评价中的噪声限值均是等效连续A声级。合成A声级采用的计算公式在首次使用前应进行验证。在背景噪声超标的情况下,应加大对风亭、冷却塔的消声降噪程度。在设计中还应充分重视冷却塔的选址以及准确识别声环境类别的重要性。

The environmental impact assessment of urban rail transit HVAC engineering over acoustical environment and air quality focuses on the wind pavilion, cooling tower and so on, attention should be given to the concept accurace of the relative terms in engineering design. The noise protection distance mentioned in the ＂Code of Metro Design＂ is based on conventional equipment, but in case of need,low noise equipment and other noise reduction measures may be adopted. Since the noise limits in rail transit environment assessment are equivalent continuous A weighted sound pressure level, the calculation formula of synthetic A weighted sound pressure level should be verified before using. When the background noise exceeds the limits, the wind pavilion and cooling tower noise reduction measures should be strengthened. In the design, more attention should be paid to the location of cooling tower and the accurate identification of the sound environment category as well.