Wind Turbine Icing
The success and increased demand for renewable energy produced by wind has led to turbine siting and wind project developments in colder climate regions both in Europe and North America. Colder climate regions are attractive to wind energy because of good wind resources combined with an increased air density of >10% compared to hot and dry climates. However, wind turbines can be subject to several atmospheric icing events during a winter season. While atmospheric icing events may only last for a few hours or days, the adverse effects associated with altered blade aerodynamics and decreased power production due to accreted ice shapes can last for weeks after the event. – In collaboration with the Adverse Environment Rotor Test Stand (AERTS, Dr. Jose Palacios) in the Department of Aerospace Engineering at Penn State we were able to perform the first scaled ice accretion experiments on a rotating wind turbine blade [Han et al., JWEIA 109 (2012)]. A combined aerodynamic- and icing scaling methodology was developed to link the unique dataset to actual operating conditions on full-scale wind turbines.
In addition, our group is working on a Turbine Icing Operation Control System (TIOCS), a coupled methodology of ice accretion modeling, iced airfoil analysis, and wind turbine performance quantification. The objective of TIOCS is to understand how blade aerodynamics changes during an atmospheric icing event, and, more importantly, what strategies can be devised to i) minimize the amount of ice accretion, and ii) safe operation at controlled loads post event, both by means of altered blade pitch and rotor speed control.
We are using the NASA Lewice code for modeling ice accretion in combination/comparison with experimental data obtained in AERTS. Alterations in airfoil characteristics due to accreted ice shapes is quantified by in-house Computational Fluid Dynamics (CFD) simulations as well as correlation tables available in the literature. Our group’s XTurb-PSU code is used for wind turbine performance analysis.
