Numerical investigation of fluidic micro-oscillators

A fluidic micro-oscillator operated with water, which can be used to control a linear tool was designed and simulated using finite element methods (FEM). In order to adjust the performance of the fluidic oscillator to the tool, a basic oscillator design was varied in terms of supply nozzle geometry and length of the feedback channels. It was found that characteristic parameters such as frequency, volume flow and output pressure depend strongly on the nozzle geometry, while with the lengthening of the feedback channels only the oscillation ability deteriorated. This led to the conclusion that in the case of micro-oscillators the period of oscillation is mainly determined by the switching time from one attachment wall to another, which is dependent on the flowrate, while the transmission time through the feedback channels, which is determined by the sonic speed.