Cross-flow turbines: integrated physical and numerical model studies towards improved array simulations

 Cross-flow, or vertical-axis turbines, show potential in marine hydrokinetic (MHK) and wind energy applications. As turbine designs mature, the research focus is shifting from individual devices towards improving turbine array layouts for maximizing overall power output, i.e., minimizing wake interference, or taking advantage of constructive wake interaction for cross-flow turbines.

Experiments were carried with large laboratory-scale cross-flow turbines, D~O(1m), using a high-resolution turbine test bed in a large cross-section tow tank, designed to achieve sufficiently high Reynolds numbers for the results to be Reynolds number independent with respect to turbine performance and wake statistics, such that they can be reliably extrapolated to full scale and used for model validation. Turbines of varying solidity were employed, including the UNH Reference Vertical Axis Turbine (RVAT) and a 1:6 scale model of the DOE-Sandia Reference Model 2 (RM2) turbine.  To improve parameterization in array simulations, an actuator line model (ALM) was developed to provide a computationally feasible method for simulating full turbine arrays inside Navier-Stokes models. Results are presented for the simulation of performance and wake dynamics of axial- and cross-flow turbines and compared with experiments and body-fitted mesh, blade-resolving CFD.

The main research seminar will be followed by a few “shorts” – 1 slide/1minute – that will give brief summaries of other research projects on wind and tidal energy, as well as motivation for future projects.

Martin Wosnik is an Associate Professor in Mechanical and Ocean Engineering and Associate Director of the Center for Ocean Renewable Energy at the University of New Hampshire. His research is in the area of fluid and thermal sciences with an emphasis on the fluid dynamics of renewable energy applications, including marine renewable energy conversion (tidal, wave, offshore wind), turbulent flows, high-speed hydrodynamics and cavitation. Dr. Wosnik has led several research deployments of tidal energy conversion devices and received a National Science Foundation CAREER award to study turbulent inflow and wakes relevant to marine hydrokinetic energy conversion.

Dr. Wosnik received a B.S. equivalent in Mechanical Engineering from the Technical University of Darmstadt, Germany, and a M.S. in Aerospace Engineering and a Ph.D. in Mechanical Engineering, both from the University at Buffalo, The State University of New York.


Thursday, April 13, 2017 - 2:30pm
E-lab 2 Kellogg Room (Room 118)