Simulation and experiment on the dynamic characteristics of a fluidic oscillator with feedback channels

Abstract

This Paper describes the dynamic behavior of a fluidic oscillator. This fluidic element, which can be used to actuate or control micro devices, was investigated by a monotone stremline upwind finite-element simulation as well as an experiment. The element, if its size is several millimeters, might be used as a kind of a micro-intelligent actuator without any moving parts and electricity. A fluidic oscillator treated here has two feedback channels. A periodic switching between two output ports is achieved by feeding back a part of flow. The dynamic behavior of the oscillator, whose nozzle width is 1 mm, was described. A fluidic oscillator experiment was carried out using water. The oscillation frequency is found to be dependent on supply volume flow rate and has a lower limit of frequency. Amplitude of pressure oscillation is also dependent on supply volume flow rate. To investigate the dynamic behavior of the fluidic oscillator, numerical simulation was carried out and the resuits were compared with those by measurement. A fluid jet keeps winding shape while the jet is switching. The relation between oscillation frequency and supply volume flow rate shows the same tendency as that of experiment.