A shock-fitting approach for predicting the two-phase transient flows in stormwater systems (SWS) with best management practices (BMP)

城市排水基础设施的设计者和管理者都意识到，由于流动能量和连续性方程的简化表示，现有的方法在复杂情况下（快速变化的流量，瞬态流量等）使用时是有限的。拟议的研究计划的目标是开发一套数值工具，用于计算暴雨水系统（SWS）的水动力条件，其中最佳管理实践（BMP）可以集成。这些工具将考虑到所有的流动类型，包括瞬态流动、空气的存在、非永久性摩擦、同时存在的多个加压/降压波、边界条件的复杂性以及人孔中的储水量。所提出的数值工具的动态行为有望更好地表征洪水情景中SWS的瞬态流动，并将这些新知识整合到当前的水管理洪水方法和新SWS的水力设计中。此外，本研究旨在解决涉及城市排水基础设施的管理人员和设计师所关心的几个问题。因此，确定了四个具体目标：(1)含夹持气穴的混合瞬态流动动力学的实验分析；(2)BMP在SWS中的集成及其对两相瞬态流动发生的影响；(3)针对更复杂和实际的SWS情况，提出一种基于激波拟合方法的方法；(4)修正瞬态流动区域的控制方程；(5)建立激波捕获和激波拟合技术的选择准则。最终，该项目旨在开发和提供可集成到现有SWS模型中的计算工具（针对每个确定的特定目标）。这项建议项目的研究结果（将包括在科学论文、数值工具和SWS指南中）将对未来和当前可持续SWS的设计过程产生重要影响。工程师需要有效的设计指南，以确保SWS的设计充分保证公众和环境的安全。加拿大咨询和市政工程师意识到可持续和长寿命排水系统设计的过渡现象。

Designers and managers of urban drainage infrastructure are aware that available current methods are limited when used in complex cases (rapidly varying flows, transient flows, etc.) because of a simplified representation of the flow energy and continuity equations. The goal of the proposed research program is to develop a set of numerical tools for calculating hydrodynamic conditions in Storm Water Systems (SWS) where Best Management Practices (BMP) may be integrated. These tools will take into account all flow types including transient flows, the presence of air, the non-permanent friction, the simultaneous presence of more than one wave of pressurization/depressurization, the complexity of boundary conditions and the water storage in manholes. The dynamic behaviour of the proposed numerical tools is expected to better characterize transient flows in SWS during flood scenarios and to integrate this new knowledge to current methods of water management flood and hydraulic design of new SWS. Moreover, the present study is intended to address several concerns from managers and designers involved with urban drainage infrastructure. Therefore, four specific objectives have been identified: (1) Experimental analysis of the dynamics of mixed transient flow with entrapped air pockets, (2) Integration of BMP in SWS and their impact on the occurrence of two-phase transient flows, (3) Development of a proposed method based on the shock-fitting approach for more complex and practical SWS cases, (4) Modifying the governing equations of the transient flow region and (5) Establishment of selective criteria of shock-capturing and shock-fitting techniques. Ultimately, the project aims to develop and offer computational tools (for each of the identified specific objectives) that can be integrated into existing SWS models. The findings of this proposed project (to be included in scientific papers, numerical tools and SWS Guidelines) will have an important impact on the design procedure of future and current sustainable SWS. Engineers require efficient design guidelines to ensure that SWS are adequately designed to guarantee the safety of the public and the environment. Canadian consulting and municipal engineers are aware of the transition phenomenon for sustainable and long lifespan drainage systems' design.