ICICLE: A Model for Glaciated & Mixed Phase Icing for
Application to Aircraft Engines 2019-01-1969
High altitude ice crystals can pose a threat to aircraft engine compression and combustion systems. Cases of engine damage, surge and rollback have been recorded in recent years, believed due to ice crystals partially melting and accreting on static surfaces (stators, endwalls and ducting). The increased awareness and understanding of this phenomenon has resulted in the extension of icing certification requirements to include glaciated and mixed phase conditions. Developing semi-empirical models is a cost effective way of enabling certification, and providing simple design rules for next generation engines. A new model is presented in this paper. It is modular in design, comprising a baseline code consisting of an axisymmetric or 2D planar flowfield solution, Lagrangian particle tracking, air-particle heat transfer and phase change, and surface interactions (bouncing, fragmentation, sticking). The model improves on those available in the literature in three ways: firstly, an adaptation of the Extended Messinger Model (EMM) to mixed phase conditions is incorporated, improving the fidelity of the ice accretion prediction compared with the classical Messinger model; secondly, an experimentally-derived model for sticking efficiency improves the accuracy of the continuity equation in the EMM; thirdly a simple model for integrating two-way coupling of mass and energy is proposed. Results from the model are compared to simple geometries tested in the NRC Research Altitude Test Facility.
Alexander Bucknell, Matthew McGilvray, David Gillespie, Xin Yang, Geoffrey Jones, Benjamin Collier
University of Oxford, Rolls-Royce Plc
International Conference on Icing of Aircraft, Engines, and Structures