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Description
A full unsteady Navier Stokes Equation (NSE) solver (known as the laminar model in FLUENT) is used to simulate a confined jet in crossflow (JICF) with Reynolds numbers (Re) in the range 287-2478. Reynolds Averaged Navier Stokes (RANS) equations are used to simulate JICF with Re in the range 4930-20000. Velocity ratios range between 0.84-3.15. Results of using the SST [lower case kappa] -- [lower case omega] or Realizable [lower case kappa] -- [lower case epsilon] are presented. Comparison to experimental data provided by the Air Force Research Lab shows that both the full NSE and RANS equations compare well with experimental data. The SST [lower case kappa] -- [lower case omega] predicts higher velocities than the Realizable model. The full Navier stokes simulation captures the major JICF vortical structures including the Counter-rotating Vortex Pair (CVP), upstream and downstream shear layers, horseshoe vortices, and hanging vortices. Many of these vortical details are lost in the RANS simulation. Two parametric studies on varying density ratio and momentum flux ratio are conducted. Varying density ratio is found to have little to no effect on the jet trajectory in the near-jet region. A lower density ratio leads to a higher Re which increases unsteadiness and turbulence which leads to improved mixing. Increasing momentum flux ratio generally increases jet penetration. However, a JICF with a larger boundary layer can penetrate deeper into the crossflow than a thinner boundary layer JICF even if the momentum flux ratio is smaller. Contributions of this work include providing additional simulation data for JICF at the presented flow conditions as well as validation of two RANS turbulence models and a full Navier Stokes solver.
