Evaluation of the shallow water ice profiling sonar for measuring frazil ice

由于河水的流动，河中冰层的形成与湖上冰层的形成有很大的不同。气流中的湍流导致一种特殊的冰粒子的形成，这种冰被称为巴西冰，它在最初形成时非常“粘”。这些脆弱的颗粒往往会相互粘在一起，粘在取水口的金属屏风和架子上，粘在河床上的岩石上，甚至粘在河中的植被上。这对水电设施以及市政和工业供水来说都是一个严重的问题，因为大量巴西水的积累会完全堵塞进水口，迫使工厂关闭。电力系统和供水的中断造成了巨大的社会经济成本。目前，我们可以使用一种相对较新的设备来探测巴西，这种设备被称为浅水冰剖面声纳（SWIPS），它的工作原理很像“寻鱼器”。然而，它只表明了冰冻的存在，并没有提供任何冰冻量的测量，这对于操作目的（因此可以操作取水以避免冰冻堵塞）和规划目的（作为预测冰冻问题和解决方案的计算机模型的输入）都很重要。拟议研究的目的是开发一种使用SWIPS仪器精确测量冰的性质（包括浓度）的方法。这将通过进行一系列受控的实验室实验来实现，以确定SWIPS数据与巴西冰性质之间的定量关系。此外，将使用Athabasca河的SWIPS收集现场数据，以演示这项新技术在现场的应用。当与数值冰过程模拟相结合时，这将为新技术提供验证。本研究的结果将通过在学术期刊上发表的方式进入公共领域。因此，这项技术将向所有人开放，并广泛使用。鉴于巴西冰沉积和运输对河流冰水力学和冬季溪流生态的压倒性意义，对加拿大的好处不能被夸大。

The formation of an ice cover in a river is quite different from that on a lake because of the river's current.  The turbulence in the flow causes the formation of a special kind of ice particle, known as frazil ice, which is very 'sticky' when first formed.  These frazil particles tend to stick to each other, to metal screens and racks at water intakes, to rocks on the river bed, and even to vegetation in the river.  This can be a serious problem for hydro-power utilities as well as for municipal and industrial water supplies, since large accumulations of frazil can completely block the intakes, forcing plants to shutdown.  These disruptions to power systems and water supplies have significant socioeconomic costs.At the present time we can detect frazil using a relatively new device known as the Shallow Water Ice Profiling Sonar (SWIPS) which works much like a 'fish finder'.  However, it only indicates the presence of frazil ice and does not provide any measure of the amount of frazil, which is important both for operational purposes (so water intakes can be operated to avoid frazil ice blockage) and for planning purposes (as an input to computer models for predicting ice problems and solutions).  The purpose of the proposed study is to develop a method for making accurate measurements of frazil ice properties, including concentration, using the SWIPS instrument.  This will be achieved by conducting a series of controlled laboratory experiments to determine the quantitative relationship between the SWIPS data and frazil ice properties.  In addition, field data will be collected with the SWIPS in the Athabasca River to demonstrate the application of this new technology in the field.  When coupled with numerical ice process modeling, this will provide validation of the new technology.The findings of this study will reside in the public domain, through publication of the research results in scholarly journals.  Thus the technology will be open to all, and widely available. Given the overwhelming significance of frazil ice deposition and transport to river ice hydraulics and to winter stream ecology the benefits to Canada cannot be overstated.