In order to study its wet natural frequency (in water) and dry frequency (in air), we conducted a two-year measurement campaign by deploying a full-scale prototype tidal current turbine system. A theoretical model is validated, and reveals the measured wet natural frequency of the device could be 54.6% of the dry frequency. Among short-term physics, inflow turbulence is important in the excitation of system resonances that can lead to fatigue damage and system failure. Among long-term physics, the wet natural frequency is highly dependent on tidal constituents, the semi-diurnal tides (M2 and S2) and diurnal tides (K1 and O1).
Revised: February 24, 2015 |
Published: July 14, 2014
Citation
Li Y., J. Yi, H. Song, Q. Wang, Z. Yang, N.D. Kelley, and K. Lee. 2014.On the Natural Frequency of Tidal Current Power Systems - A Discussion of Sea Testing.Applied Physics Letters 105, no. 2:Article No. 023902.PNNL-SA-100413.doi:10.1063/1.4886797