Oscillating Airfoil Icing Tests in the NASA Glenn Research Center Icing Research Tunnel 2011-38-0016
A team from the USA rotorcraft industry, NASA, and academia was established to create a validated high-fidelity computational fluid dynamics (CFD) icing tool for rotorcraft. Previous work showed that an oscillating blade with a periodic variation in angle of attack causes changes in the accreted ice shape and this makes a significant change in the airfoil drag. Although there is extensive data for ice accumulation on a stationary airfoil section, high-quality icing-tunnel data on an oscillating airfoil is scarce for validating the rotorcraft icing problem. In response to this need, a two-dimensional (2D) oscillating airfoil icing test was recently performed in the Icing Research Tunnel at the NASA Glenn Research Center. Three leading-edge specimens for an existing 15-inch chord test apparatus were designed and instrumented to provide the necessary data for the CFD code validation. The test apparatus was run in steady and oscillatory operation mode to collect data for variations in liquid water content, tunnel temperature, and airspeed. Data obtained from the test include ice tracings, photographs, surface pressure measurements, wake traverse data, and force balance data. This paper presents an overview of the test including model details, test instrumentation, sample results, and a summary of key findings.