Numerical simulation of synthetic jet actuators

A promising design of fluid actuators for flow control is investigated. Two-dimensional, incompressible simulations of synthetic jet actuators are performed. A modeled boundary condition is developed for the actuator. Three different velocity distributions along the orifice are examined and all three distributions give qualitatively similar flow features. Both laminar and turbulent jets are investigated. Results show very good agreement with experimental measurements. A jet flow develops, even though no net mass flow is introduced. Pairs of counterrotating vortices are observed near the jet exit as are observed in the experiments. Comparison of the synthetic jet computations is made with both pulsed jets and steady jets. Little difference is seen in the turbulent flow regime, but the laminar flow shows markedly different results between a steady jet and a synthetic jet. It has been demonstrated that the modeled boundary condition captures the essential features of the jet without modeling the detailed breakdown of the vortices or the details of the cavity flow. Nomenclature