Ice Crystal Ingestion in a Turbofan Engine 2015-01-2146

A through-flow based Monte Carlo particle trajectory simulation is used to calculate the ice crystal paths in the low pressure compressor of a high bypass ratio turbofan engine. The simulation includes a statistical ice particle breakup model due to impact on the engine surfaces. Stage-by-stage ice water content, particle size and particle velocity distributions are generated at multiple flight conditions and engine power conditions. The majority of the ice particle breakup occurs in the fan and first LPC stage. The local ice water content (IWC) within LPC is much higher than the ambient conditions due to scoop effects, centrifuging and flow-path curvature. Also the ice particles approach the stators at lower incidence angles than the air flow. The simulation results prompt the need to revisit the approach for properly setting up boundary conditions for component or cascade testing.