Topic: On The Detrimental Effects of Snow and Icing Weather on Wind Turbines

Dr. Hui Hu is the Martin C. Jischke Professor of Aerospace Engineering at Iowa State University. He received his BS, MS, and PhD in Aerospace Engineering from the Beijing University of Aeronautics & Astronautics (BUAA) in China, and a PhD in Mechanical Engineering from the University of Tokyo in Japan. His recent research interests include advanced optical/laser-based diagnostics, aircraft/aero-engine icing and anti-/de-icing technology; wind energy and wind turbine aeromechanics; Fluid-Structure Interactions (FSI) of built structures in violent windstorms (e.g., tornadoes, downbursts, and snowstorms). Dr. Hu is an ASME Fellow and AIAA Associate Fellow. He is serving as an editor of “Experimental Thermal and Fluid Science-Elsevier” and an associate editor of “ASME Journal of Fluid Engineering” and “ASME Open Journal of Engineering”. He is the recipient of several prestigious awards, including 2006 NSF-CAREER Award, 2007 Best Paper in Fluid Mechanics Award (Measurement Science and Technology, IOP Publishing), 2013 AIAA Best Paper Award in Ground Testing Technology, 2014 Renewable Energy Impact Award of Iowa Energy Center, 2022 AIAA Best Paper Award on Gas Turbine Engine, and 2023 D.R. Boylan Eminent Faculty in Research Award of Iowa State University. Further information about Dr. Hu’s technical background and research activities is available at: http://www.aere.iastate.edu/~huhui/

Abstract: Adverse weather such as snow, freezing rain, and sleeting has been found to pose a significant threat to the efficiency and integrity of wind turbines operating in cold climates. A field campaign in a 50 MW mountainous wind farm to investigate the detrimental effects of snowing/icing events on the performance of multi-megawatt (1.5MW) wind turbines by using a Supervisory Control and Data Acquisition (SCADA) system and an Unmanned-Aerial-Vehicle (UAV) equipped with a high-resolution digital camera will be introduced at first. Then, by leveraging the unique Icing Research Tunnel available at Iowa State University (i.e., ISU-IRT), a comprehensive experimental campaign was conducted to characterize the detrimental effects of snow, freezing rain, and sleeting weather on the performance of wind turbines and elucidate the underlying physics. A suite of advanced flow diagnostic techniques, which include molecular tagging velocimetry and thermometry (MTV&T), digital image projection (DIP), and infrared (IR) imaging thermometry, were developed and applied to quantify the impinging dynamics of airborne snowflakes and supercooled water droplets, transient behavior of wind-driven water film/rivulet flows, unsteady heat transfer, dynamic ice accretion process over the surfaces of wind turbine blades. The potentials of bioinspired hydro-/ice-phobic coatings, including lotus-inspired superhydrophobic coatings and pitcher-plant-inspired Slippery Liquid-Infused Porous Surfaces (SLIPS), to mitigate the detrimental effects of snow/ice accretion are evaluated under various test conditions. A novel hybrid strategy that combines minimized surface heating near the blade leading edge and hydro-/ice-phobic coating was developed for wind turbine snowing/icing protection with substantially less power consumption (i.e., up to ~90% power saving).