An experimental campaign was conducted to study dynamic ice accretion on rotating aeroengine fan blades and evaluate the icing-induced performance degradation to the fan rotor. The experiments were performed in an icing research tunnel with a scaled spinner-fan model exposed to typical dry rime and wet glaze icing conditions. Although the accreted ice layers were found to conform well with the shapes of the fan blades under the rime icing condition, the performance of the fan rotor was found to degrade substantially due to the much rougher blade surfaces, causing up to 60% reduction in the pressure increment after 360 s of the rime icing experiment. More complicated, needlelike icicles were found to grow rapidly over the rotating spinner and fan blades under the glaze icing condition due to the combined effects of the aerodynamic forces and the centrifugal forces associated with the rotation motion. The irregular-shaped glaze ice structures were found to induce tremendous detrimental effects on the fan rotor, making the airflow depressurized, instead of pressurized, after passing the iced fan rotor. The iced spinner-fan model was always found to consume more power, regardless of rime or glaze ice structures accreted on the fan blades.
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This content will become publicly available on June 8, 2024
An Experimental Study to Characterize the Effects of Ice Accretion on the Aerodynamic Performance of an Offshore Wind Turbine Blade Model
The accretion of ice on the surface of a wind turbine blade causes a drastic reduction in the aerodynamic performance and as a result, the power output, in addition to posing a safety hazard. To quantify this phenomenon, an experimental study was conducted in the Iowa State University Icing Research Tunnel (ISU-IRT) to understand the dynamic ice accretion process and resultant aerodynamic performance degradation specifically experienced by offshore wind turbines at higher Liquid Water Content (LWC) levels. Four different LWC values were tested for both glaze and rime ice conditions each, to cover the possible spectrum of typical icing conditions. A high-speed imaging camera was used to capture the dynamic ice accretion process, while a Digital Image Projection (DIP) technique was used to perform the 3D qualification of the ice accretion characteristics. Two highly sensitive multi-axis force and moment transducers were used to measure the lift and drag forces acting upon the airfoil. The lift force was found to decrease, and the drag force was found to increase with the formation of ice. The amount of change in the unsteady aerodynamic forces was found to depend on the ambient temperature, the LWC, as well as the accreted ice structure.
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- Award ID(s):
- 2140489
- NSF-PAR ID:
- 10491099
- Publisher / Repository:
- American Institute of Aeronautics and Astronautics
- Date Published:
- Journal Name:
- AIAA AVIATION 2023 Forum
- Subject(s) / Keyword(s):
- ["Wind turbine icing physics\nOffshore wind turbine\nIcing-induced wind turbine performance degradation\nWind Turbine icing mitigation"]
- Format(s):
- Medium: X
- Location:
- San Diego, CA and Online
- Sponsoring Org:
- National Science Foundation
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