矩形配水池流場及濃度場結構數值分析

Numerical analysis of flow field and concentration field in a rectangular reservoir

孫忠言

指導教授 ： 林誠興博士

元智大學/工程學院/機械工程學系/碩士(2000年)

摘要

自來水係由供水機構將水源地的水，經過導水設備送至淨水場，經混合、膠凝、沉澱、過濾消毒等淨水處理程序，以除去水中的雜質及病菌，再經配水系統送至消費者家中。於配水系統中配水池的功能為保持供水時有足夠的水壓、水量及避免為外界污染。但配水池會因不良操作或設計導致水質變壞，也就是使配水池內水的水齡增高。消毒劑含量過低，殺菌不徹底會使微生物菌增高或過多的氯消毒而增加消毒副產物等而影響人體健康及安全。目前於配水池中一般使用氯消毒，而氯在被水池中混合效果就與配水池內部之流場有密切的關係。但配水池為一密閉空間我們對池內流場結構及混合狀況無法直接觀察，故了解不多。本文主要是利用PHOENICS套裝軟體來分析矩形配水池內流場及濃度場結構，並規劃出三個模型來分別討論，希望藉由不同位置之進水口、不同進水速度、不同寬度之進水口及增設導流牆數量來探討這些參數的改變對配水池流場及濃度場變化之影響。

關鍵字

矩形配水池 ； 紊流 ； 濃度場

並列摘要

Piped water is conveyed from rivers to water purification plant where water is treated by a series of purification processes such as mixing, coagulation, sedimentation , filtration and disinfection to remove impurities and pathogens. Then, water is sent to every family through a distribution system. In the distribution system, reservoir is utilized to maintain sufficient water pressure, and to prevent environmental contamination. To improve the water quality chlorine is commonly used in the reservoir for disinfection. Well mixing of chlorine with water is important and associated with water flow pattern with in reservoir. Because the reservoir is a closed space, the flow pattern and actual mixing in the reservoir cannot be observed and measured directly. In this thesis, PHOENICS was utilized to investigate the effects of various design parameters on the flow pattern and concentration of a rectangular reservoir. Tri-design conditions include different locations of inlet and outlet, inlet flow rates, sizes of inlet, and number of baffles.

並列關鍵字

rectangular reservoir ； turbulent flow ； concentration field

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