Yuntong She at University of Alberta

River ice processes

Ice plays a critical role in most northern rivers as it affects the river's ecosystems, as well as water quality and water quantity. The greatest hazard caused by river ice is associated with ice jam events (accumulations of broken ice floes) which can often result in severe and hard-to-predict flooding. Hydro-peaking operations can be severely constrained on regulated rivers during freeze-up season due to the risk of breaking and consolidating the fragile developing ice covers. Such flow restrictions result in lost revenue to hydro-power companies and can have environmental implications as well. In addition, river ice has important implications for transportation networks in Canada since ferries (during open water season) and ice bridges (during ice covered season) are essential transportation links for many northern communities. River ice have the potential to greatly affect the mode and timing of the transportation across and along the rivers. The expected climate change further underscores these issues.

Some important research topics include but not limit to:

Impact of climate change on river winter regime
Effects of river regulation on on river ice regime
Ice jam flood forecasting

Pipe flow simulation

The world's pipeline network is massive. Even with extensive regulation and pipeline companies taking many measures to maintain and monitor their pipelines to ensure safe operations, there is always a possibility that a leak could occur. Oil pipeline leaks can result in significant environmental impacts and huge economic losses. Enhancing current leak detection technologies is highly desirable as it may improve response to a leak event, thus reducing the environmental and economic losses. Among the wide variety of leak detection techniques, real-time transient model based leak detection method has the advantage of being relatively non-invasive and requiring no field installation. The occurrence of a leak creates a transient event that may be possible to detect by analyzing the hydraulic behavior of the pipeline system. The governing equations are solved by a computer model to calculate the hydraulic state of the pipeline in real time. The pipeline state is indicated by the measurements from field sensors, provided to the leak detection system by the supervisory control and data acquisition (SCADA) system. A comparison between the computed and measured hydraulic states can indicate whether a leak is present.

Considering the real-world challenges that the model based leak detection method faces, it is important to investigate:

Effect of uncertainties on the performance of model based leak detection system
Enhancement of existing model based leak detection system

New research has been started on layering Artificial Intelligence with physical-based model for leak detection.

Groundwater/surface water interaction

The hyporheic zone is an active region where the surface water and the groundwater interact and exchange. Due to the large hydraulic, chemical, and biological gradients between the two water bodies, water and solute continuously going in and out of the zone, making it a biogeochemical hot spot. Three-dimensional models have been used to characterize this important flow region; however, these models need extreme efforts to set up, large amount of and some time hart to obtain input data. We have been working on developing simplified and more practical methods that can provide comparable results as the more sophisticated models.

River bank erosion protection

Geotextile sand filled bags (geobags) are often used for erosion protection and flood control in river and coastal engineering. They are price competitive, environment-friendly, and can be more stable in the long term as compared to some conventional materials. We are developing a better formula for sizing the geobags. CFD modelling, laboratory experiments and field observations will be conducted. This will significantly reduce the construction cost and risk of flood damage. The outputs will greatly increase the possibility of using geobags as a primary way to protect eroding river banks.