人们普遍认为 在配送过程中，水质可能会恶化 微生物和化学系统 本体相和/或管道中的反应 墙水质恶化的一个严重方面 在网络中是消毒剂的损失 会削弱屏障的残余物 防止微生物污染。目的 这项研究的目的是为了解决免费软件的丢失问题 腐蚀金属和聚乙烯中的氯 氯化物（PVC）管道可能会发生以下变化: 速度研究表明，在老年人中 无衬里金属管，氯残留消失 速度加快但 在PVC管中保持稳定。 从报道的实验中可以清楚地看出 在这篇文章中有不同之处 墙与墙之间的需求特征 无衬里金属管和PVC管 差异具有监管含义。这个 作者还发现，虽然 系统建模是一项重要的活动 应该保持甚至扩大，不是吗 模型是完美的，公用事业公司必须保持 精心构建的校准程序 使用模型时。包括30个参考文献、表格和图表。

It has become generally accepted that water quality can deteriorate in a distribution system through microbiological and chemical reactions in the bulk phase and/or at the pipe wall. A serious aspect of water quality deterioration in a network is the loss of the disinfectant residual that can weaken the barrier against microbial contamination. The purpose of this study was to address the loss of free chlorine in corroded metal and polyvinyl chloride (PVC) pipes subject to changes in velocity. The study demonstrated that in older unlined metal pipes, chlorine residuals disappear rapidly with increased velocity but remain stable in PVC pipe. It is clear from the experiments reported in this article that there are differences between the wall demand characteristics of unlined metallic and PVC pipe and that these differences have regulatory implications. The authors also found that although distribution system modeling is an important activity that should be maintained and even expanded, no model is perfect and utilities must maintain a carefully constructed calibration program when models are used.Includes 30 references, tables, figures.