Experimental and numerical study on stagnation point offset of turbulent opposed jets

The stagnation point offsets of turbulent opposed jets at various exit velocity ratios and nozzle separations were experimentally studied by a hot-wire anemometer, smoke-wire technique and numerically simulated by Reynolds stress model (RSM). Results show that for 2D <= L <= 4D (where L is nozzle separation and D is nozzle diameter), the position of the impingement plane is unstable and oscillates within a region between two relative stable positions when the exit velocities are equal. However, the impingement plane deviates from the midpoint obviously and the flow field becomes stable relatively when there is very small difference of the exit velocities for opposed jets of 2D <= L <= 8D. At L <= 2D or L > 8D, the position of stagnation point becomes insensitive to the variety of exit velocity ratio. (C) 2007 Elsevier B.V. All rights reserved.