This paper describes the experimental and numerical investigations of a very low head (VLH) water-turbine model downstream of a step profile, as encountered during installation in existing structures. In particular there is an interest to study the pressure profile at the turbine inlet based on the effect of turbine placement downstream of the steppedbed profile. The experimental procedure, outlining the methodology to obtain qualitative and quantitative information on the flow behavior, is presented. A comparison of experimental data with numerical modeling is performed. As well dye visualizations are used to provide a better understanding of the flow behavior in this region. It can be concluded from this investigation that the VLH turbine will experience an 8% drop in pressure on the lower 30% of the turbine face at a distance x/d=0 from the step, likely with adverse affects on turbine performance. Although the lower 30% of the turbine face is still affected by a recirculation zone at distances of x/d=0.5 and greater from the step profile, only a 4% pressure drop is observed and therefore would likely not have a major effect on turbine performance.
|Title of host publication||Proceedings of the 23rd CANCAM|
|Publication status||Published - 2011|
|Event||23rd Canadian Congress of Applied Mechanics 2011 - Vancouver, BC, Canada|
Duration: 5 Jun 2011 → 9 Jun 2011
|Conference||23rd Canadian Congress of Applied Mechanics 2011|
|Period||05/06/2011 → 09/06/2011|