I.A. Milne, A.H. Day, R.N. Sharma, and R.G.J. Flay – 18th Australasian Fluid Mechanics Conference, December, 2012
This paper presents results from an experimental study which analysed the hydrodynamic response of the out-of-plane blade root bending moment for a horizontal-axis turbine exposed to multi-frequency oscillatory motion. Estimates of the amplitude and phase agree well with those for single frequency oscillatory motion, which suggests that a model based on the principles of linear superposition is applicable. When minor flow separation is experienced, linear superposition is likely to offer conservative estimates. The findings are likely to be of interest to designers of turbines deployed in tidal streams, rivers or canals, and who are seeking low computational approaches for assessing the dynamic blade loads.