下水道渠管網與邊溝市街流耦合演算之研究

Abstract

構築較符合真實街道外貌之邊溝市街流系統，建立下水道系統與邊溝銜接之連結管交換算則，並說明交換機制運算方式。利用NewC下水道渠管網演算模式，引用人孔處可能會發生跌水之情況、針對模擬真實案例時可能會碰到單管系統修正之方法，結合連結管交換算則，進行下水道系統與邊溝市街流耦合模擬演算，證實模式之可用性。 本研究第一部份建立下水道與邊溝系統交換機制，計算陡坡連結管問題。利用Normann等人(1985)提出之入口控制經驗公式，計算陡坡入口控制問題；改寫入口潛沒公式，使之能明確表達物理行為；運用能量方程式，推導連結管下游控制及逆坡問題之側入流交換量演算法。降雨落到街道上後，往街道旁之邊溝匯集，經由連結管排入下水道系統；下水道若無法順離排水造成滿管，通常是經由連結管流至邊溝，若邊溝無法順利排水則滿溢而出形成市街流，待下水道系統退水時，無法順利排出之水可能會再經由連結管回到下水道系統中。建立連結管交換機制，測試其適用性。 本研究第二部份主要目的為針對現有的NewC下水道模式，考慮人孔處可能會發生跌水情況，引入使用視水位取代人孔水位進行模擬演算；針對模擬真實案例時可能會碰到單管系統，須修正控制方程式的係數矩陣；結合連結管交換算則，進行下水道渠管網系統與邊溝市街流聯合模擬演算，經由模擬結果顯示，連結管交換算則確實可應用於下水道與邊溝市街系統中模擬。

Establishing a gutter-street flow system more in line with the real street appearance, building a computing algorithm of connective pipe for coupling sewer and gutter-street systems, and using some cases to introduce how the exchange works. Using NewC sewer network model, citing the theory freefall may occur in manhole, and a method of revising coefficients matrix of one-branch system, combined with links to control the exchange operator, to carry out cases simulation, confirmed the model could be used . Part I: Establishing the flow exchange algorithm of sewer and gutter-street system, using experiment formula by Normann et al(1985), and change equation’s term into a more make sense way. Using energy equation to derive an algorithm of outlet control and inverse slope problems. After the rain fell on the streets, the water will gather to the gutter and run through the pipe into the sewer system. If the drainage system can’t work, it will make the sewer become the full pipe situation, and the flow is usually flow from sewer system into gutter-street system. The sewer system could work again after the flood released. Establishing a computing algorithm of connective pipe for coupling sewer and gutter-street systems to prove this model could work. Part II: Solving problems of the theory freefall may occur in manhole and a method of revising coefficients matrix of one-branch system, using appearance water level to replace the water level of manhole to computation. Combining the exchange algorithm,, confirmed the model could be used . Keyword: NewC scheme, Normann experiment equations, sewer, gutter-street, connective pipe, coupling.