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A primary goal of large eddy simulation, LES, is to capture in-cylinder cycle-to-cycle variability, CCV. This is a first step to assess the efficacy of 35 consecutive computed motored cycles to capture the kinetic energy in the TCC-III engine. This includes both the intra-cycle production and dissipation as well as the kinetic energy CCV. The approach is to sample and compare the simulated three-dimensional velocity equivalently to the available two-component two-dimensional PIV velocity measurements. The volume-averaged scale-resolved kinetic energy from the LES is sampled in three slabs, which are volumes equal to the two axial and one azimuthal PIV fields-of-view and laser sheet thickness. Prior to the comparison, the effects of sampling a cutting plane versus a slab and slabs of different thicknesses are assessed. The effects of sampling only two components and three discrete planar regions is assessed.

Three-dimensional time-dependent calculations are performed to investigate the compressible turbulent flow about a train passing through a single-track tunnel. The “snapper” algorithm in KIVA-3 is used to allow the train to pass through the stationary tunnel mesh. Actual train geometry is simplified considerably. The length of the train/tunnel as well as the speed of the train is considered to investigate their effects on the train-tunnel interaction. In an effort to understand the whole process of the train-tunnel aerodynamic interaction, the formation and propagation of the pressure waves, the radiation and reflection of the waves at the tunnel portals and the histories of aerodynamic forces on the train are studied. The experimental results compare well with the computational data.