Computational Modeling of Synthetic Jets

D.C. Durán, and O.D. López
Universidad de los Andes, Bogotá, Colombia

A synthetic Jet actuator is a device which moves a fluid in and outside a cavity, through a small aperture, by the continuous oscillation of a diaphragm. The multiphysics interaction between the piezoelectric disk, which deforms due to the alternating voltage, and the fluid makes COMSOL Multiphysics the most suitable tool for the computational analysis of these devices. The first approach to the problem was to validate the behavior of the piezoelectric disk through a tridimensional model, showing satisfactory results. An axisymmetric model of the complete synthetic jet actuator was used to analyze the influence of low frequencies and the aperture size in the synthetic jet formation. For this analysis, we used the Piezo Axial Symmetry, Incompressible Navier-Stokes and Moving Mesh ALE physics interfaces. Numerical results of this model show a strong dependence of the synthetic jet formation on the size of the aperture. All these observations are of great help in synthetic jet device research and development, and encourage further multiphysics simulations and analysis of these actuators.