Characterizing Turbulence Anisotropy, Coherence, and Intermittency at a Prospective Tidal Energy Site


As interest in marine renewable energy increases, observations and models are crucial to understanding the environments encountered by energy conversion devices. Data obtained from an acoustic Doppler velocimeter in the Puget Sound, WA are used to perform a detailed analysis of the turbulent environment that is expected to be present at a turbine placed in a tidal strait. Metrics such as turbulence intensity, coherent turbulence kinetic energy, and a new scalar measure of anisotropy are used to characterize the turbulence coherence, intermittency and anisotropy. The results indicate that the scalar anisotropy magnitude can be used to identify and parameterize coherent, intermittent turbulent events in the flow. An analysis of the anisotropy characteristics leads to a physical description of turbulent stresses as being dominated by only one- or two-dimensions, and parameterized best by anisotropy magnitude. Furthermore, turbulence generated by the National Renewable Energy Laboratory’s TurbSim model is analyzed with these characteristics of anisotropy, testing the ability of the model to create realistic turbulent environments.

Dec 10, 2013 3:30 PM — 4:30 PM
Bechtel Collaboratory, Discovery Learning Center
Engineering Center, University of Colorado at Boulder, Boulder, CO 80309

University of Colorado Boulder