Computational study of different turbulence models for air impingement jet into main air cross stream

Jets impinging into main air cross streams in the transfer of heat and mass into or from working fluid to the wall are applied in cooling techniques, rocket launcher cooling, piston lubrication, high density dryers, pneumatic conveying, and gas turbine cooling. The common impact between the jet and the main cross stream is analyzed at various jets by means of cross-flow velocity ratio calculations. In the current study, an air stream impinges perpendicularly with an assortment of velocity ratios into a main cross stream, which is brought out through a 10 cm diameter pipe until the Reynolds number reaches 6 × 10⁴. The flow pattern is simulated numerically with the two-equation turbulence models: Realizable k-ε, SST k-ω, and RSM l. Reynolds Averaged Navier Stokes modeling is frequently encountered in many industrial applications, in which the reliability of the simulation and the computational time conserving are required. Our study demonstrates that the jet pattern is misshaped as the standard speed is expanded and detachment regions are created. More turbulent intensity and massive flow stresses occurs immediately after the touch down the regular face between the jet and cross stream. Comparison of numerical and experimental results indicate that the flow velocity field is best described by the Realizable k-ε turbulence model. The Reynolds fluxes show divergent trends from the experimental results. The introduced CFD model equations provided quantitative assessments of model errors and judgments of model suitability versus referenced experimental data.