Steady-state and unsteady Reynolds-averaged Navier-stokes modelling of cold jets-in-hot crossflow in a cylindrical duct for non-impinging, impinging, and strongly impinging jets

The objective of this study is to demonstrate that strongly impinging jets-in-crossflow (JIC) will result in a counter flowing jet that will probably be unsteady. This numerical study was conducted in a 360 o (complete cylindrical duct) computational domain using a steady-state Reynolds-Averaged Navier Stokes, RANS, and time-dependent URANS at various momentum-flux ratios J. Asymmetry in a steady-state RANS solution is very likely to be an indication of the flow’s instability and unsteadiness. RANS predictions clearly show asymmetry in cases of strongly impinging jets. RANS solutions show that steady-state solutions are not appropriate if the flow is, or is suspected to be, unsteady. RANS and URANS solutions for computational domains