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Three-dimensional simulations of the Honeywell ALF502 low pressure compressor (sometimes called a booster) using the NASA Glenn code GlennHT have been carried out. A total of eight operating points were investigated. These operating points are at, or near, points where engine icing has been determined to be likely. The results of this study were used, in a companion paper, for further analysis such as predicting collection efficiency of ice particles and ice growth rates at various locations in the compressor. In an effort to minimize computational effort, inviscid solutions with slip walls are produced. A mixing plane boundary condition is used between each blade row, resulting in convergence to steady state within each blade row. Comparisons of the results are made to other simplified analysis. An additional modification to the simulation process is also presented.

A flow and ice particle trajectory analysis was performed for the booster of the Honeywell ALF502 engine. The analysis focused on two closely related conditions one of which produced an icing event and another which did not during testing of the ALF502 engine in the Propulsion Systems Lab (PSL) at NASA Glenn Research Center. The flow analysis was generated using the NASA Glenn GlennHT flow solver and the particle analysis was generated using the NASA Glenn LEWICE3D v3.63 ice accretion software. The inflow conditions for the two conditions were similar with the main differences being that the condition that produced the icing event was 6.8 K colder than the non-icing event case and the inflow ice water content (IWC) for the non-icing event case was 50% less than for the icing event case.

A new technique is proposed for computing particle concentrations and fluxes with Lagrangian trajectories. This method calculates particle concentrations based on the volume of a parcel element, or cloud, at the flux plane compared against the initial volume and is referred to as the Lagrangian Parcel Volume (LPV) method. This method combines the steady-state accuracy of area-based methods with the unsteady capabilities of bin-based methods. The LPV method results for one-dimensional (1D) unsteady flows and linear two-dimensional (2D) steady flows show that a quadrilateral element shape composed of a single parcel (with four edge particles) is capable of accurately predicting particle concentrations. However, nonlinear 2D flows can lead to concave or crossed quadrilaterals which produce significant numerical errors.

Particle trajectory and ice shape calculations were made for the Energy Efficient Engine (E₃) using the LEWICE3D Version 3 software. The particle trajectory and icing computations were performed using the new "block-to-block" collection efficiency method which has been incorporated into the LEWICE3D Version 3 software. The E₃ was developed by NASA and GE in the early 1980s as a technology demonstrator and is representative of a modern high bypass turbofan engine. The E₃ flow field was calculated using the NASA Glenn ADPAC turbomachinery flow solver. Computations were performed for the low pressure compressor of the E₃ for a Mach .8 cruise condition at 11,887 meters assuming a standard warm day for three drop sizes and two drop distributions typically used in aircraft design and certification. Particle trajectory computations were made for water drop sizes of 5, 20 and 100 microns.