Active decoupling of the axisymmetric body wake response to a pitching motion

Abstract Controlled interactions between fluidic actuators and the cross flow over the aft end of a wire-mounted axisymmetric wind tunnel bluff body model ( Re D =2.3·10 5 ) are exploited for modification of the near wake dynamics, and the consequent global aerodynamic loads. Actuation is effected using an array of four aft-facing synthetic jet modules through narrow, azimuthally-segmented slots that are equally distributed around the perimeter of the tail end. The model is supported by eight wires, each including a miniature inline force transducer for measurements of the time-resolved tension. The model’s position is varied in a prescribed trajectory by synchronous activation of shape memory alloy (SMA) segments in each of the mounting wires, and the aerodynamic forces and moments are manipulated over a range of pitch attitude. The effectiveness of the flow control approach is demonstrated by decoupling of the wake response from the body’s pitch motion at a low pitch frequency ( k =0.013). It is shown that, under the active control, the wake symmetry can be restored or its asymmetry can be amplified.

[1]  M. Amitay,et al.  Aspects of low- and high-frequency actuation for aerodynamic flow control , 2005 .

[2]  Jiezhi Wu,et al.  Post-stall flow control on an airfoil by local unsteady forcing , 1998, Journal of Fluid Mechanics.

[3]  Michael Amitay,et al.  Aerodynamic control using synthetic jets , 2000 .

[4]  Thomas C. Corke,et al.  Radius Flow Vectoring for Projectile Drag and Steering Control Using Plasma Actuators , 2008 .

[5]  Christopher S. Rinehart,et al.  Aerodynamic forces induced by controlled transitory flow on a body of revolution , 2011 .

[6]  C. Murphy.  Symmetric Missile Dynamic Instabilities , 1981 .

[7]  Mukund Acharya,et al.  The mechanism of flow control on a cylinder with the unsteady bleed technique , 1991 .

[8]  Ari Glezer,et al.  Fluidic Control of Aerodynamic Forces on a Bluff Body of Revolution , 2012 .

[9]  Charles E. Tinney,et al.  Axial flow over a blunt circular cylinder with and without shear layer reattachment , 2006 .

[10]  Ron Barrett,et al.  Design and testing of piezoelectric flight control actuators for hard-launch munitions , 2004, SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring.

[11]  Christopher J. Elkins,et al.  Separation control in a conical diffuser with an annular inlet: center body wake separation , 2010 .

[12]  Matthew P. Cartmell,et al.  One-dimensional shape memory alloy models for use with reinforced composite structures , 2003 .

[13]  Mark Costello,et al.  Simplified Projectile Swerve Solution for General Control Inputs , 2008 .

[14]  I. Wygnanski,et al.  Oscillatory Blowing: A Tool to Delay Boundary-Layer Separation , 1993 .

[15]  Charles H. Murphy.  Some special cases of spin-yaw lock-in , 1987 .

[16]  J. Nicolaides.  A history of ordnance flight dynamics , 1970 .

[17]  S. Nemat-Nasser,et al.  Superelastic and cyclic response of NiTi SMA at various strain rates and temperatures , 2006 .

[18]  M. Amitay,et al.  Aerodynamic Flow Control over an Unconventional Airfoil Using Synthetic Jet Actuators , 2001 .

[19]  Ari Glezer,et al.  Transitory Force Development on a Body of Revolution Using Synthetic Jet Actuation , 2003 .

[20]  Jubaraj Sahu,et al.  TIME-ACCURATE COMPUTATIONS OF FREE-FLIGHT AERODYNAMICS OF A SPINNING PROJECTILE WITH AND WITHOUT FLOW CONTROL , 2006 .

[21]  Fei-Bin Hsiao,et al.  Forcing level effects of internal acoustic excitation on the improvement of airfoil performance , 1992 .

[22]  Michael Amitay,et al.  MODIFICATION OF LIFTING BODY AERODYNAMICS USING SYNTHETIC JET ACTUATORS , 1998 .

[23]  Ari Glezer,et al.  Direct measurements of controlled aerodynamic forces on a wire-suspended axisymmetric body , 2011 .

[24]  Mark Costello,et al.  Model Predictive Control of a Direct Fire Projectile Equipped With Canards , 2008 .

[25]  D. A. Price.  Sources, mechanisms, and control of roll resonance phenomena for sounding rockets. , 1967 .

[26]  Ari Glezer,et al.  Microadaptive Flow Control Applied to a Spinning Projectile , 2004 .

[27]  F. Hsiao,et al.  Control of wall-separated flow by internal acoustic excitation , 1990 .

[28]  Robert J. Englar,et al.  Circulation Control Pneumatic Aerodynamics: Blown Force and Moment Augmentation and Modification; Pa , 2000 .

[29]  Jonathan B. Freund,et al.  Drag and wake modification of axisymmetric bluff bodies using Coanda blowing , 1994 .