Particle Trajectory and Icing Analysis of the E
Turbofan Engine Using LEWICE3D Version 3
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. Particle trajectory and ice shape predictions were made for a 20 micron Langmuir-D distribution and for a 92 micron Super-cooled Large Droplet (SLD) distribution with and without splashing effects for a Liquid Water Content (LWC) of .3 g/m₃ and an icing time of 30 minutes. The E₃ fan and spinner combination proved to be an effective ice removal mechanism as they removed greater than 36% of the mass entering the inlet for the icing cases. The maximum free stream catch fraction for the fan and spinner combination was 0.60 while that on the elements downstream of the fan was 0.03. The non-splashing trajectory and collection efficiency results showed that as drop size increased impingement rates increased on the spinner and fan leaving less mass to impinge on downstream components. The SLD splashing case yielded more mass downstream of the fan than the SLD non-splashing case due to mass being splashed from the upstream inlet lip, spinner and fan components. The ice shapes generated downstream of the fan were either small or nonexistent due to the small available mass and evaporation except for the 92 micron SLD splashing case. Relatively large ice shapes were predicted for internal guide vane #1 and rotor #1 for the 92 micron SLD splashing case due to re-impingement of splashed mass.