Effects of Noncircular Inlet on the Flow Structures in Turbulent Jets

Abstract

Turbulent jet flows with noncircular nozzle inlet are investigated by using a Reynolds Stress Model. In order to analyze the effects of noncircular inlet, the cross section of inlet are selected as circular, square, and equilateral triangular shape. The jet half-width, vorticity thickness, and developments of the secondary flow are presented. From the result, it is confirmed that the secondary flows of square and equilateral triangular nozzle are more vigorous than that of the circular jet. This development of secondary flows is closely related to the variations of vortical motions in axial and azimuthal directions.

Influence of jet temperature and nozzle shape on the heat transfer distribution between a smooth plate and impinging air jets

“…be attributed to smaller length of the potential core for triangular jet. Kim and Park [11] report that the potential core length is around 7.8d e for triangular free jet, 8.4d e for square free jet and 9.8d e for circular free jet at a Reynolds number of 21,000. Singh et al [10] corroborate this by reporting higher decay rates for triangular and square free jets compared to that of circular free jets at a Reynolds number of 7200.…”

“…The local heat transfer distribution over the impingement plate shows axis switching of jet by counter flow vortices which are present at the corners of noncircular nozzles. Kim and Park [11] reported development of axial flow distribution for circular, square and triangular shapes at different z/d e by contour plots. Present Nusselt number contour plots are in good correlation with the results reported by Kim and Park [11] at corresponding z/d e .…”

“…Singh et al [10] and Kim and Park [11] reported influence of nozzle shape (square and triangular) on flow structure of free jet. Investigations on non-circular and circular free jets by Singh et al [10] suggest that the axial velocity decay is faster for square and triangular jets compared to the circular jets.…”

“…Investigations on non-circular and circular free jets by Singh et al [10] suggest that the axial velocity decay is faster for square and triangular jets compared to the circular jets. Kim and Park [11] studied circular, square and equilateral triangle free jets numerically. They suggested that for square and triangle jets secondary flow is more dominant compared to that in circular jet.…”

Comparison of Flow Field Simulation of Liquid Ejector Pump using Standard K-ε and Embedded LES Turbulence Modelling Techniques

“…The methodology helped in determining the equivalence ratio which effectively induce secondary flow (Hoke et al 2002). The effect of different geometrical configurations of primary flow inlets on the turbulent flow regime of jets was investigated using Reynolds Stress Model and it was concluded that development of the triangular jets is stronger than others (Kim and Park, 2013).…”