Control of two‐dimensional turbulent wall jet on a coanda surface

Abstract

The Coanda effect that is the tendency of a fluid jet to stay attached to an adjacent curved surface that is very well shaped has been employed to improve the performance of various devices. The main objective of this paper is to investigate ways of keeping the flow attached to a larger length of a Coanda surface. There are considered two possibilities: one passive, which uses a slot that connects the low pressure and high pressure points on the Coanda surface and an active one, based on the principle of synthetic jet, created through an orifice located near the point of detachment of the jet. Reynolds averaged Navier‐Stokes simulations (RANS) with shear stress transport k‐ω (SST model) of Menter have been used to compute the two‐dimensional turbulent wall jet. The numerical results are presented for the two methods considered. (© 2011 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Coanda Effect on the Flows Through Ejectors and Channels

“…There are several works [1]- [5] investigating the mechanism through which the secondary flow is induced in the ejector. In this paper the authors study the various flow patterns inside the Coandă ejector and the effect of various design parameters on the mass flow rate of the induced flow numerically.…”

“…Mechanical deflection of the thrust involves engine nozzle deflection and, thus, physically modify of the main flow direction [5,6], but this can used complicatelly devices and actuators. Alternative method to mechanical deflection can be done using a secondary jet to entrainment the main jet (Fig.…”