Experimental Studies of Dynamic River Ice Processes

河冰堵塞是许多加拿大社区的主要关切，因为它们对生命和财产都构成了重大威胁。冰塞是危险的，因为它们可以非常迅速地形成，并且通常比公开水域事件(例如塞尔柯克，MB)导致更高的洪水水位。它们还会迅速释放，造成危险的冰浪和水浪(例如，阿肯色州麦克默里堡)。2009年红河结冰造成的洪水使该省防洪基础设施的极限变得紧张，因为没有足够的预测模型，不得不匆忙开发，以应对迅速上升的水位。据估计，洪水期间的水位在4个小时内上升了1.22米，总上升了2.8米。这促使政府斥资440万美元买断红河沿岸易发洪水的物业，因为水位的急剧上升使当地居民很难充分发出警告。*能够预测和检查这些动态冰川过程的影响是很重要的，这样利益相关者就可以解决公共安全、优化水电运营和对水环境的影响等问题。然而，数值模型仍然处于开发阶段，主要是因为它们依赖于基于经验关系而不是实际流动物理的子程序。冰的输运和积聚对冰塞的形成具有重要意义，由于单个浮冰周围复杂的流体动力学，冰的输运和积聚被认为是河流冰工程中最复杂的问题之一。目前，我们对这些过程的许多知识必然是定性的，因为在实地测量动态冰过程时会出现固有的后勤困难和安全问题。对于冰塞下的浮冰运输来说，情况尤其如此。*拟议研究计划的目标是研究河流冰塞动力学，以促进我们对这些过程的基本知识，包括更好地了解个别浮冰的运输和冰塞的形成。这将为其他人目前正在开发的数值模式提供必要的验证，并扩大我们实施具有更大物理基础的改进的数值模式的能力。四名研究生将在这项研究计划下通过一系列创新实验接受培训，他们将成为加拿大未来的河冰水力学专家。**

River ice jams are of major concern to many Canadian communities as they pose a significant threat to both lives and property. Ice jams are dangerous because they can form very rapidly, and typically cause higher flood levels than open water events (e.g. Selkirk, MB). They can also release quickly, creating dangerous surges of ice and water (e.g. Fort McMurray, AB). Flooding in 2009 caused by ice jams on the Red River strained the limits of the province's flood control infrastructure as adequate predictive models were not available and had to be hurriedly developed in response to rapidly increasing water levels. It is estimated that water levels during the event rose 1.22 m in 4 hours, with a total rise of 2.8 m. This prompted a $4.4 million buyout program for flood-prone properties along the Red River as the dramatic rise in water level made it difficult to adequately warn the local residents.***It is important to be able to predict and examine the impacts of these dynamic ice processes so that stakeholders can address issues such as public safety, optimized hydroelectric generation operations, and effects on the aquatic environment. However, numerical models remain in the development stage primarily because of their reliance on subroutines that are based on empirical relationships rather than actual flow physics. The transport and accumulation of ice is of great importance to the formation of ice jams and is considered one of the most complicated problems in river ice engineering because of the complex fluid dynamics surrounding individual ice floes. At present, much of our knowledge of these processes is necessarily qualitative, due to the inherent logistical difficulties and safety issues that arise when trying to measure dynamic ice processes in the field. This is particularly true for ice floe transport under ice jams. ***The objective of the proposed research program is to investigate river ice jam dynamics to advance our fundamental knowledge of these processes, including a better understanding of the transport of individual ice floes and the formation of ice jams. This will provide essential validation for numerical models currently being developed by others and expand our ability to implement improved numerical models that have a greater physical basis. Four graduate students will be trained under this research program through a series of innovative experiments and will become some of Canada's future experts in river ice hydraulics.**