Effect of the Oscillator Length on the Characteristics of a Feedback Type Fluidic Oscillator

Abstract

This work characterizes the various length fluidic oscillators with constant depth and having the same main geometric dimensions. A change in fluidic oscillator's length affects the frequency and sweeping characteristics of the fluidic oscillators. These characteristics were extracted by means of constant temperature anemometry hot-wire measurements and water flow visualizations. A total number of ten fluidic oscillators were compared to the baseline fluidic oscillator design. It was observed that shortening the fluidic oscillator ceases the oscillations after a threshold oscillator length whereas elongating the fluidic oscillator decreases the frequency and sweep angle gradually. Furthermore, the frequency maps obtained from hot-wire measurements for each considered fluidic oscillator design provided overall detail about the frequency of the oscillations for a wide range of flow rate. For a constant supply flow rate where the frequency and the sweep angle of an oscillator is constant, changing the length of a fluidic oscillator will allow varying these characteristics of the oscillator. Thus the oscillator can be tailored for a specific need of an application.