Our aim in this paper is to present a brief overview of the scaled hydrokinetic turbine model testing activities in the United States using test turbines specifically designed by the US Department of Energy for its Marine and Hydrokinetic Research and Development program. These test turbines include: (1) a three-bladed horizontal axis turbine (the Sandia turbine) that was designed to demonstrat...

Free stream tidal turbines are rotating bodies in fast flowing tidal currents, and as such are exposed to fluctuating loads from the surrounding fluid. These time varying forces will cause the blades to deform dynamically, potentially deflecting the blade shape away from the optimum orientation as well as exciting resonant responses that may enhance fatigue loading. It is important to understan...

Tidal stream speeds in straits are accelerated because of geographic and bathymetric features. For instance, narrow channels and shallows can cause high tidal stream energy. In this study, water level and tidal current were simulated using a three-dimensional semi-implicit Eulerian-Lagrangian finite-element model to investigate the complex tidal characteristics in the Taiwan Strait and to deter...

A brief review of the literature is provided on the characteristics of marine currents and the approaches used for simulating tidal turbines. The feasibility of using CFD models to simulate time-dependent turbulent flow around a tidal turbine is then explored. Two different approaches for specifying the structure of the turbulent inflow conditions in CFD models are compared: the von Kármán spec...

The diffuser total efficiency was formulated and defined based on the generalized actuator disc model for index of diffuser-alone diffuser-augmented wind turbines. An optimization method to maximize developed using a genetic algorithm axisymmetric computational fluid dynamics. A case study conducted 10% chord-to-diameter ratio, 2% thickness-to-chord plate, crest position at 50% chord diffuser. ...

Numerical investigations have been carried out on 35% scaled down model of PGT10 gas turbine exhaust diffuser under the condition of with inlet guidevanes and without struts. Numerical simulations were carried out to determine the static pressure development and pressure recovery, by varying the area ratio and divergence angles varying from θ = 7 to 13 by keeping the diffusion length constant. ...

Recent development in using wind turbines for urban areas results inserting inside buildings. As buildings' walls may act as a duct the turbine, this study focuses on ducted turbine with fixed geometry. A method is organized achieving improved generated power and speed augmentation geometry of regardless type which aim building designers. Using porous disc (PD) instead rotor makes cost time eff...