Ice Accretion Prediction on Engine Nacelles in Liquid Phase Clouds

Özgen, Serkan
Görgülü, İlhan
Tatar, Volkan
More than a hundred in-flight incidences have been reported in the last two decades related to icing on aircraft engine components including rollbacks, mechanical failure and flameouts [1, 2]. Thus, in-flight ice accretion on aircraft engine components and nacelles has been attracting more interest, especially from the airworthiness certification point of view. Computer simulations as well as ground and flight tests are among the means of compliance for airworthiness certification related to safe flight in icing conditions. Although current certification requirements define icing conditions in terms of liquid phase clouds only, recent occurrences have necessitated to extend this envelope to include solid phase and mixed phase clouds, encountered in high altitude convective clouds both for airframes and engines [3, 4]. The present study aims at predicting ice accretion on engine nacelles in liquid phase clouds. Such an effort would also allow the prediction of impingement limits and impingement rates required for the design of ice protection systems. Although there is a wealth of experimental and numerical data for wings and airfoils in the literature, such data for nacelle or intake geometries are scarce. As with most computational tools developed for this purpose, the current tool comprises four main modules; modules for flow-field solution, droplet trajectories and collection efficiencies, thermodynamics and ice accretion. The flow-field solution is accomplished by a panel method modified for nacelle geometries and required engine mass flow rates, while the ice accretion module employs the extended Messinger model [5]. The manuscript summarizes the methods used in the developed computational tool that is being constantly extended with new capabilities since around 8 years, followed by the results obtained for benchmark geometries and flow conditions available in the literature. The results include the collection efficiencies for different flight and cloud conditions, as well as the actual ice shapes obtained for those conditions. Effects of SLD on collection efficiencies and ice accretion are also brought out. Comparisons with experimental and numerical data are also presented for the cases for which these are available.
SAE 2015 International Conference on Icing of Aircraft Engines and Structures, 22 - 25 Haziran 2015


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Citation Formats
S. Özgen, İ. Görgülü, and V. Tatar, “Ice Accretion Prediction on Engine Nacelles in Liquid Phase Clouds,” presented at the SAE 2015 International Conference on Icing of Aircraft Engines and Structures, 22 - 25 Haziran 2015, Prag, Çek Cumhuriyeti, 2015, Accessed: 00, 2021. [Online]. Available: