The CFPM lab is actively involved in Marine Renewable Energy Research, mostly investigating in-line hydrokinetic energy generation from rivers, tidal flows, and ocean currents. Many of our simulations and methodologies also apply to wind energy.
Our capabilities provide high-fidelity computational fluid dynamics (CFD) of time-dependent and unsteady hydrodynamics at the rotor/blade level, and also within the wake. This includes fluid-structure interactions and active control of geometry and/or kinematic motion.
A sample of previous projects are illustrated below.
Intracycle Control of Cross-Flow Turbines
Simulations of cross-flow turbines are performed to look at the vortex dynamics within the cycle, and how the performance can be enhanced by actively modifying the angular velocity. By applying a sinusoidal angular velocity profile, the power coefficient is increased by modifying the vortex dynamics and relative flow vectors. Continued work in this area includes blockage/confinement effects, and assessment of various modeling strategies (e.g. RANS vs. LES). Experimental collaborators include Professors Brian Polagye and Owen Williams at the University of Washington.
Oscillating Foil Arrays
Oscillating foils in a heaving and pitching motion are able to generate energy from an incoming flow in a similar manner as traditional rotation-based turbines. Unlike traditional turbines, they leave behind a structured wake from the large, coherent vortices shed at each half-cycle. Research is being performed into how to optimize the kinematics and configurations of close-packed arrays of oscillating foils, in order to improve the energy density. Computational fluid dynamics is utilized along with machine learning techniques. Experimental collaborators include Professor Kenny Breuer at Brown University.
Active On-Blade Flow Control
High Reynolds number (Re=400,000) large-eddy simulations (LES) are utilized to investigate the effect of dielectric barrier discharge (DBD) plasma actuators in the boundary layer of a wind turbine airfoil. Various actuation strategies along the trailing edge are explored in order to modify the lift curve, which can be utilized to mitigate unsteady loads on blades in off-design conditions. Collaboration with Arctura Inc (formally Aquanis).