Numerical Simulation of Fluidic Actuators for Flow Control Applications

Abstract

Active flow control technology is finding increasing use in aerospace applications to control flow separation and improve aerodynamic performance. In this paper we examine the characteristics of a class of fluidic actuators that are being considered for active flow control applications for a variety of practical problems. Based on recent experimental work, such actuators have been found to be more efficient for controlling flow separation in terms of mass flow requirements compared to constant blowing and suction or even synthetic jet actuators. The fluidic actuators produce spanwise oscillating jets, and therefore are also known as sweeping jets. The frequency and spanwise sweeping extent depend on the geometric parameters and mass flow rate entering the actuators through the inlet section. The flow physics associated with these actuators is quite complex and not fully understood at this time. The unsteady flow generated by such actuators is simulated using the lattice Boltzmann based solver PowerFLOW R . Computed mean and standard deviation of velocity profiles generated by a family of fluidic actuators in quiescent air are compared with experimental data. Simulated results replicate the experimentally observed trends with parametric variation of geometry and inflow conditions. Nomenclature

Numerical Study of Internal Flow Structures in a Sweeping Jet Actuator

“…However, the internal flow field of such devices has only been examined by two experimental 4, 5 and four numerical [21][22][23][24] studies. The fluidic actuators investigated in these studies vary by type, geometry, working fluid, etc.…”

“…The fluidic actuators investigated in these studies vary by type, geometry, working fluid, etc. So far, there is just one numerical study 24 , which employs the Lattice-Boltzman based PowerFLOW solver, available in the literature for the interior flow field of a sweeping jet actuator.…”

Performance Enhancement of a Vertical Tail Model with Sweeping Jet Actuators

“…Recently, these devices were used in aeronautical experiments for the purpose of delaying separation on airfoils [6][7][8] and on wings [9]. The usefulness of these devices prompted the need to understand how they work [10] and their effect on boundary layers that are about to separate from the surface. In the interim one may improve the efficiency of these actuators for a specific application by using dimensional analysis that enables one to determine the leading parameters controlling the process [11,12] and this is approximately the manner in which they were applied presently.…”

Flow Separation Control on a Full-Scale Vertical Tail Model using Sweeping Jet Actuators

“…Recently, these devices were used in aeronautical experiments for the purpose of delaying separation on airfoils 15-17 and on wings. 18 The usefulness of these devices prompted the need to understand how they work 19,20 and their effect on boundary layers that are about to separate from the surface. In the interim, one may improve the efficiency of these actuators for a specific application by using dimensional analysis that enables one to determine the leading parameters controlling the process 21,22 and this is approximately the manner in which they were applied presently.…”

“…3 The capabilities of AFC have been demonstrated on airplane and component models in many laboratory and/or aerodynamic environments. [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] Rathay et al 4,5 applied synthetic jet actuators to a subscale (~7%) vertical stabilizer model, where actuators placed next to the hinge of the rudder produced up to 20% side force increase at moderate rudder deflections. Seele et al 6,7 applied the sweeping jet actuators to a subscale (~14%) vertical tail model.…”