A numerical investigation into the effects of positioning and rotation on the performance of two vertical-axis hydrokinetic turbines
|Kuhn, David (Mechanical Engineering) Zhang, Qiang (Bio-systems Engineering)
|Bibeau, Eric (Mechanical Engineering) Wang, Bing-Chen (Mechanical Engineering)
|Master of Science (M.Sc.)
|Numerical simulation allows investigation into the influence of separation distance and rotation on the performance of two vertical-axis hydrokinetic turbines. Compu- tational fluid dynamics is applied to calulate the lift and drag coefficients acting upon interacting NACA 0021 turbine blades for a Reynolds number of Red = 10, 000. To understand the effect of separation distance, large-eddy simulation of the flow around side-by-side and staggered cylinders, ReD = 3,000, and airfoils, Rec = 3,000, are also performed. Based upon the simulations, a drag reduction of 11.3% and 19.8% is determined for the downstream cylinder and airfoil, respectively. A reduction in Reynolds stresses is also observed for the staggered configuration compared to the side-by-side configuration. Due to computational resources of large-eddy simulation, the Reynolds averaged Navier-Stokes method is also applied to investigate the influence of separation distance and rotation on two vertical axis hydrokinetic turbines. The numerical simulations show that a drag reduction of 15.5% occurs when the non-dimensional spanwise and streamwise separation distances, based on turbine diameter, reach 1 and 2, respectively.
|renewable energy, hydrokinetic turbines, turbine interactions, numerical, computational fluid dynamics, large eddy simulation
|A numerical investigation into the effects of positioning and rotation on the performance of two vertical-axis hydrokinetic turbines