Experimental study of offset and reattached turbulent jets

该研究项目将与马尼托巴省水电公司的工程师密切合作，致力于彻底了解与湍流三维偏置射流相关的复杂流动动力学。这种流动在环境和工程上有着广泛的应用，包括暖通空调系统、工业废物处理、水力发电站下游的换热和能量消散。 研究范围很广，包括雷诺数、偏置比、不对称比、接收通道粗糙度、下游尾水位、膨胀比和喷嘴类型。大型设施(宽1.5米，长7米，深0.95米)的测量将包括沿通道的压力分布，使用非分散染料的流动显示，以及使用声学多普勒测速仪的水流速度。还将使用粒子图像测速技术在较小的水道(0.2米宽、2.5米长和0.2米深)中进行几何相似的小规模试验。 在这个项目中进行的测量将是迄今为止对三维偏置喷流进行的最完整的调查。它们将作为基准数据库，以促进能够处理这种复杂流动条件的湍流模型的开发和验证。这样的模型将对水利工程师非常有益，使他们能够在其电站下游设计更有效和更经济的消能结构。他们还将能够更准确地量化和预测溢洪道的下游影响。 在整个项目中，将为一名博士、一名硕士、两名本科生和一名技术员提供培训。

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.