Synchronization of a Pair of Opposed Facing Oscillators in a Side-by-Side Configuration

Abstract

This study considers two opposed facing fluidic oscillators in a side-by-side layout. Each fluidic oscillator shares one of its feedback channels with the other oscillator thus this configuration provides a mean for communication between fluidic oscillators. As a result of this communication through the shared feedback channel, the exiting jets of the fluidic oscillator pair are synchronized. The details of this synchronization are revealed by means of hot-wire measurements, flow visualizations and validated numerical simulations. The oscillation frequencies for both jets were the same and varied from 123 Hz to 476 Hz for a flow rate range from 5 SLPM to 25 SLPM per inlet corresponding to Reynolds number range of 2,125 to 10,625. The calculated cross-correlation coefficients were over 0.88 for the considered flow rate range. The flow visualizations exposed that the exiting jet of each fluidic oscillator move away from the shared feedback channel and move toward the shared feedback channel simultaneously indicating motion in the same direction. Numerical results indicated that the shared feedback channel plays a pressure balancing role while allowing inter-oscillator flow through each side of the shared feedback channel thus controlling the flow direction of each exiting jet yielding a synchronized output from the fluidic oscillator nozzles.