Experimental study of offset and reattached turbulent jets

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In close collaboration with engineers from Manitoba Hydro, this research project will endeavour to provide a thorough understanding of the complex flow dynamics associated with turbulent three dimensional offset jets. This type of flow has diverse environmental and engineering applications, including HVAC systems, industrial waste disposal, heat transfer and energy dissipation downstream of hydroelectric generating stations. A wide range of parameters will all be investigated, including Reynolds number, offset ratio, asymmetry ratio, receiving channel roughness, downstream tailwater level, expansion ratio and nozzle type. Measurements in a large-scale facility (1.5 m wide, 7 m long, 0.95 m deep) will include pressure distribution along the channel, flow visualization using a non-dispersive dye, and water velocity using an acoustic Doppler velocimeter. A geometrically-similar small-scale test will also be conducted in a smaller channel (0.2 m wide, 2.5 m long and 0.2 m deep) using particle image velocimetry techniques. The measurements that will be taken during this project will comprise the most complete investigation of three dimensional offset jets to date. They will serve as a benchmark data base to facilitate the development and verification of turbulence models capable of handling such complex flow conditions. Such models will be extremely beneficial to hydraulic engineers; allowing them to design more effective and economical energy dissipation structures downstream of their stations. They will also be able to more accurately quantify and predict the downstream effects of their spillways. Throughout the project, training will be provided to one Ph.D., one M.Sc., and two undergraduate students as well as one technician.