This flume is relatively long and deep flume because it was designed for understanding how coarse sand and gravel sediment transport occurs under a shear stress applied from moving water. The uniqueness of the facility relative to others available in the world is that we are able to track sediment transport from underneath the bed of the flume, which allows the measurements to be made during the experiments, giving us potentially much greater understanding of the temporal and spatial details of this complex process. The higher depth of the facility allows for good characterization of the flow boundary layer.
- 18.3 m long x 1.2 m wide x 0.60 m deep;
- Slope is adjustable from 2% to -0.5%;
- Gravel sized sediment tracking from a custom-built Radio Frequency Identification (RFID) carriage that moves back and forth underneath the bed of the flume to non-intrusively locate sediment particle tracers during an experiment (Hufnagel and MacVicar, 2018, JHE). To ensure that particles can be reliably detected and precisely located, Wobblestones were designed and constructed to hold the RFID transponders in a vertical orientation (perpendicular to the bed) in tracers that roll and saltate along the channel bed (Papangelakis et al 2019, JHE); and
- Flow measurement using a Vectrino Profiler able to measure three orthagonal velocity components at 100 Hz in a series of bins as small as 1 mm in thickness over a total sampling volume of 35 mm.
The facility has been used for a wide range of experiments including floating or submerged structures such as boats and piers, hydraulic structures such as gates, weirs, stilling basins, fish ladders, and channel pools, and modelling of sediment transport in rivers and around hydraulic structures.
Currently the channel is being modified to test sediment transport impact plates and expand its sediment feed and measurement capabilities.
This flume is relatively wide and shallow because it was designed for understanding sedimentation processes in a river and its floodplain. It can be used, for example, to understand the dynamics of braided-river bar plains, or the role of floating wood on sediment accumulation and island growth. The uniqueness of this facility is the camera trolley that allows the capture of images that can be used to reconstruct the topography of the sediment bed.
- 13.3 m long x 2.0 m wide x 0.20 m deep;
- Slope is adjustable from 2% to 0%;
- Sand and fine gravel sized sediment can be fed into this river table using a calibrated feeder and then weighed in baskets at the outlet of the flume;
- Topographic change is measured using the Structure from Motion (SfM) technique from two obliquely mounted cameras on a trolley above the flume; and
- Measurement of the water surface velocities is from Large Scale Particle Image Velocimetry (LSPIV) from an obliquely mounted camera at the water surface.
Currently the channel is being upgraded to allow the simulation of flow hydrographs and to track particles using luminescence during the experiments.
Freddy is a computer server that we use for Computational Fluid Dynamics modelling and analysis of large data sets. For example:
- ANSYS Fluent - a commercial software used to perform Large Eddy Simulation (LES) on simplified geometries of pools and riffles to visualize and understand turbulent flow structures;
- MITT - a processing and visualization tool we developed for high-frequency turbulent flow time series;
- SPIN - a stream power indexing tool for stream networks we developed to understand how urbanization may impact stream stability;
- Agisoft Photoscan - a commercial software used to process large numbers of images and turn them into orthophotos and digital elevation models that can be analysed to understand sedimentation processes in the field and lab; and
- PC-SWMM - a commercial software that works as a GIS based interface for working with the US Environmental Protection Agency's stormwater management tool.