Modelling of Two-Phase Transient Flow with multiple Surges in Storm Water Systems by the Shock-Fitting Technique

目前的雨水系统设计方法是基于能量方程和连续性方程的简化表示法。这种过于简单化的设计导致了严重的问题和对下水道的昂贵破坏(间歇泉、溢流、街道淹没、交通事故和严重的电力问题)。这些问题之一的一个例子发生在2011年的蒙特利尔，7月18日星期一，位于勒内-L和圣凯瑟琳之间的沃尔夫街上的一个沙井被变成了名副其实的间歇泉，喷出几米高的暴雨水。被堵塞在雨水管中的加压空气试图逃逸，带走了大量的暴雨水。一辆停在沙井金属盖上的汽车甚至被反复猛烈举起。 拟议的研究项目将解决这些安全问题。将建立一套有效的数值工具来计算SWS中的水动力条件，其中可能整合了最佳管理实践(BMP)。这一新方法将考虑所有流动类型，包括瞬变流动、空气的存在、非永久性摩擦、同时存在一个以上的增压/降压波、复杂的边界条件以及沙井和BMP中的水存储。个人计算机的最新进展促进了在瞬变流动模拟中纳入动态考虑。将建议在全球雨水管理解决方案中制定新的法规、水源和管道末端控制(EOP)控制准则。这一拟议项目(数值工具和SWS准则)的结果将对未来和当前可持续SWS的设计程序产生重要影响。预计使用新工具将节省大量资金，因为未来的排水系统将根据可持续标准进行设计，并且它们将导致排水系统的使用寿命更长。 Fuamba教授在过去五年中与本建议相关的研究工作促进了城市排水领域中几个数值工具的开发：(1)评估SWS中的溢流风险，(2)分析沙井容量对涌浪传播的影响，(3)SWS边界条件的模拟，(4)分析增压/降压波阵面行为和滞留气囊，以及(5)用Godunov方法模拟瞬变两相流中的非定常摩擦。他的专业知识将有助于创造一套新的工具。

Current design methods for Storm Water Systems (SWS) are based on simplified representations of energy and continuity equations. This oversimplified design of the SWS has led to severe problems and costly damage to sewers (geysers, overflows, street inundations, traffic accidents and also severe electrical problems). An illustration of one of these problems happened in Montreal in 2011, where a manhole located on Wolfe Street, between the streets René-Lévesque and Sainte-Catherine, was turned into a veritable geyser on Monday July 18th, projecting sprays of storm water several meters high. Pressurized air that was blocked in the storm sewer tried to escape, taking with it large amounts of storm water. A car parked on the manhole metal cover was even violently raised repeatedly. The proposed research project will address these safety issues. An efficient set of numerical tools will be instituted for calculating hydrodynamic conditions in SWS where Best Management Practices (BMP) may be integrated. This new approach will take note of all flow types including transient flows, the presence of air, non-permanent friction, simultaneous presence of more than one wave of pressurization/depressurization, complexity of boundary conditions and water storage in manholes and BMP. The recent progress in Personal Computer advancements promote the incorporation of dynamic considerations in the transient flows modeling. New guidelines for regulations, integration of sources and End-Of-Pipe (EOP) controls into the global storm water management solutions will be recommended. The findings of this proposed project (numerical tools and SWS Guidelines) will have an important impact on the design procedure of future and current sustainable SWS. It is anticipated that significant money will be saved when using the new tools, because future SWS will be designed according to sustainable criteria and they will result in long lifespan drainage systems. Research work carried out by Professor Fuamba during the past five years related to the present proposal has contributed to the development of a few numerical tools in the urban drainage domain: (1) to assess the overflood risk in SWS, (2) to analyze the influence of manhole capacity on the propagation of the surge wave, (3) to model the SWS boundary conditions, (4) to analyze the pressurized/depressurized wave front behaviour and trapped air pockets, and (5) to simulate unsteady friction in transient two-phase flow with Godunov method. His expertise will be helpful in the creation of the new set of tools.