密封的建筑排水系统和通气系统活性气压的瞬变控制和抑制---建筑给排水外文文献翻译.docVIP

本科毕业设计 外文文献及译文 文献、资料题目:Sealed building drainage and vent systems 文献、资料来源:国道数据库 文献、资料发表(出版)日期:2005.9.12 院 (部): 市政与环境工程学院 专 业: 给水排水工程 班 级: 姓 名: 学 号: 指导教师: 翻译日期: 2012.06 外文文献: Sealed building drainage and vent systems ?an application of active air pressure transient control and suppression Abstract The introduction of sealed building drainage and vent systems is considered a viable proposition for complex buildings due to the use of active pressure transient control and suppression in the form of air admittance valves and positive air pressure attenuators coupled with the interconnection of the networks vertical stacks This paper presents a simulation based on a four-stack network that illustrates flow mechanisms within the pipework following both appliance discharge generated, and sewer imposed, transients. This simulation identifies the role of the active air pressure control devices in maintaining system pressures at levels that do not deplete trap seals Further simulation exercises would be necessary to provide proof of concept, and it would be advantageous to parallel these with laboratory, and possibly site, trials for validation purposes. Despite this caution the initial results are highly encouraging and are sufficient to confirm the potential to provide definite benefits in terms of enhanced system security as well as increased reliability and reduced installation and material costs Keywords: Active control; Trap retention; Transient propagation Nomenclature C+-??characteristic equations c??wave speed, m/s D??branch or stack diameter, m f??friction factor, UK definition via Darcy Δh4fLu2/2Dg g??acceleration due to gravity, m/s2 K??loss coefficient L??pipe length, m p??air pressure, N/m2 t??time, s u??mean air velocity, m/s x??distance, m γ??ratio specific heats