Prediction of Ice Accumulation and Airfoil Performance Degradation: A Boeing – CIRA Research Collaboration

In 2004, a collaborative effort between The Boeing Company and CIRA, the Italian Aerospace Research Center was started to compare and establish best-practice ice accumulation and aerodynamic performance degradation prediction methods. Methodology and results obtained up to the end of 2005 are shared within. The initial step in the collaboration called for the benchmarking of the predictive methods employed by the two teams. Systematic ice accretion and performance degradation calculations were carried out across an agreed upon range of atmospheric conditions. For performance degradation, results from airfoil performance prediction tools, including Navier-Stokes solvers, are compared against test data obtained by NASA for a known ice shape on the NLF-0414 general aviation airfoil. Ice accumulation prediction tools are calibrated against published data for several icing conditions, including glaze and rime, for the NACA 0012 airfoil. Given the complexity and variability of icing effects, the success of the prediction tools is generally good; greater understanding of how to predict ice shapes and the accompanying performance degradation was obtained.