Jet interactions in a feedback- free fluidic oscillator at low flow rate

Abstract

In this work, the internal fluid dynamics and frequency characteristics of feedback-free fluidic oscillators are investigated experimentally for low flow rates below 3.4 mL/s. The internal flow field of feedback-free fluidic oscillator was extracted using a refractive index-matched Particle Image Velocimetry (PIV) technique with the help of a problem-specific sensor setup for simultaneous frequency measurements in refractive index matching fluid. The oscillation mechanism for the low flow rate region was revealed with PIV measurements. Flow topologies extracted with the measurements were found to exhibit various flow features and the details of the jets interactions and vortical balance that lead to oscillatory behavior were discussed.