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Accurate quantification of 3D shapes of the complex ice structures accreted on wind turbine blades is highly desirable to develop ice prediction models for more accurate prediction of the aerodynamic performance degradation and power reduction due to the ice accretion on wind turbine blades. In the present study, an experimental investigation was conducted to quantitatively characterize the 3D shapes of the ice structures accreted over a DU91-W2-250 wind turbine airfoil model in the Icing Research Tunnel available at Iowa State University (ISU-IRT). A glaze icing condition and a rime icing condition that wind turbines usually experience in winter were duplicated by using ISU-IRT. A high-resolution non-intrusive 3D scanning system was used to make detailed 3D-shape measurements to quantify the complicated ice structures accreted on the wind turbine airfoil model as a function of the ice accretion time.

The promising anti-icing performance of the slippery liquid infused porous surface (SLIPS) has been recently demonstrated for various engineering applications. The runback icing for aircraft and wind turbines could be effectively mitigated considering the timely removal of water droplet by the wind shearing force due to the low adhesion on the SLIPS. In this study, the flow field both inside and around the wind-driven droplet over the SLIPS was experimentally investigated by using Particle Image Velocimetry (PIV) technique. Previous studies majorly focus on the internal flow pattern before the droplet incipient motion. In this study, the flow field inside a moving droplet was firstly investigated. As a result of the low surface adhesion of the SLIPS, droplet oscillations were eliminated and the droplet internal flow field could be corrected from the optical distortion.

Atmospheric icing poses a major threat to power transmission lines in cold regions. In the present study, an experimental investigation was conducted to examine the atmospheric icing process on high-voltage power transmission lines and characterize the effects of the ice accretion on the aerodynamic forces acting on the transmission lines. The experimental study was conducted in the Icing Research Tunnel available at Iowa State University (ISU-IRT). A cylinder model with the same diameter of commonly-used high-voltage power transmission lines (i.e., D = 29mm) is subjected to a typical glaze icing condition at an incoming wind speed of 20 m/s, a liquid water content (LWC) of 2.0 g/m3 and an ambient temperature of -5 0C. A high-resolution 3D scanner was used in the present study to extract the 3D shapes of the ice structures accreted over surface of the cylindrical test model as a function of the ice accretion time.

The electro-thermal method is most commonly used for wind turbine anti-/de-icing. The upmost drawback of such systems is the high power consumption. In the present study, we proposed to use a durable slippery liquid-infused porous surface (SLIPS) to effectively reduce the power requirement of the heating element during the anti-/de-icing process. The explorative study was conducted in the Icing Research Tunnel at Iowa State University (ISU-IRT) with a DU91-W2-250 wind turbine blade model exposed under severe icing conditions. During the experiments, while a high-speed imaging system was used to record the dynamic ice accretion process, an infrared (IR) thermal imaging system was also utilized to achieve the simultaneous surface temperature measurements over the test model.

Wind turbine icing represents the most significant threat to the integrity of wind turbines in cold weather. Ice formation on wind turbine blades was found to cause significant aerodynamic performance degradation, resulting in a substantial drop in energy production. Recently developed Dielectric barrier discharge (DBD) plasma-based anti-/de-icing systems showed very promising effects for aircraft icing mitigation. In this present study, DBD plasma-based anti-/de-icing systems were employed for wind turbine icing mitigation. First, a comprehensive parametric study is conducted to investigate the effects of various DBD plasma actuation parameters on its thermodynamic characteristics. An infrared (IR) thermal imaging system is used to quantitatively measure the temperature distributions over the test plate under various test conditions.

Ice accretion on aero-engines, especially on the fan blades, is the very hazardous icing incident due to the potential performance degradation of jet-engines. In the present study, an experimental investigation was conducted to examine the performance of ice-phobic coatings for jet-engine fan icing mitigation. The experimental study was performed in the unique Icing Research Tunnel at Iowa State University (ISU-IRT) with a scaled engine fan model operated under wet glaze and dry rime ice conditions. To evaluate the effects of anti-icing coatings and to acquire the important details of ice accretion and shedding process on fan blade surfaces, a “phase-locked” imaging technique was applied with a high-resolution imaging system. The power input required to drive the engine fan model rotating at a constant prescribed speed was also measured during the ice accretion experiment.