Control of self-oscillations of a round turbulent jet propagating in a narrow rectangular cavity

Abstract

The paper presents the results of numerical simulation of a round turbulent jet propagation in confined space: the jet at Re = 5.4×10⁴ is supplied into a rectangular cavity with a height to width ratio of 0.16. The URANS and LES calculations reproduce the self-oscillating regime, registered previously in the experiments by Lawson et al. (2005). A significant rearrangement of the flow structure and pressure field occurring at a low-flow jet supply from the narrow side wall allows controlling self-oscillations up to their complete suppression. A map of flow regimes has been obtained for three various positions of the opening, supplying the control jet, depending on the control and primary jets momentum ratio. The calculated data provide a quantitative assessment of the flow controllability by injecting a low-flow jet into the zone of the primary jet propagation perpendicular to its axis.