Aerodynamic Scaling of General Aviation Airfoil for Low Reynolds Number Application

31st AIAA Applied Aerodynamics Conference

et al. 2013

Self Cite

A wing glove for active flow control free-flight experiments using a one-fifth dynamically scaled Aeromot 200S Super Ximango motor glider was developed. The wing glove has a modified NACA 643 − 618 airfoil and is instrumented with off-the-shelf pressure transducers and amplitude-modulated synthetic jet actuators. Before the flight-testing was commenced the wing glove and the instrumentation were tested in two open return low-speed wind tunnels. Due to the low-aspect ratio of the glove, particular attention was paid to the two-dimensionality of the flow field over the wing glove. Several flight experiments were carried out and free-flight data with and without actuation were recorded. Unexpected challenges that were encountered during the flight-testing are discussed and an analysis of the wall pressure data in the frequency domain is provided.

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Wind Tunnel and Free-Flight Testing of Active Flow Control for Modified NACA 613-618 Airfoil

Dianics

Balthazar

31st AIAA Applied Aerodynamics Conference

et al. 2013

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“…In addition, it eliminates the risks involved for test pilots and lowers the environmental impact. However, successful scaled flight research can only be guaranteed if the geometrically scaled model exhibits the same aerodynamics as the full size wing (aerodynamic scaling) [1] . For example, in both experiments [2] and numerical investigations [3] , it was found that at low angles-of-attack, the boundary layer separates in the aft section of the blade.…”

Section: Introductionmentioning

confidence: 99%

Control of Boundary-Layer Separation for Lifting Surfaces

Balzer

2009 DoD High Performance Computing Modernization Program Users Group Conference

Fasel

2009

The lack of understanding of most of the relevant physical mechanisms when applying flow control limits the prospects of successfully transitioning flow-control technologies into real flight vehicles. Successful control of boundary-layer separation for lifting surfaces promises major performance gains especially when large laminar runs are desired in order to minimize the skin-friction drag.We systematically explore the fundamental mechanisms of the interaction of separation and transition that are relevant for effective and efficient flow control applications.Toward this end, we are employing computational fluid dynamics (CFD) for investigating active flow control for a NACA 64 3 -618 airfoil at a chord Reynolds number Re C =64,200 and various angles-of-attack. CFD results are compared to wind/water tunnel experiments carried out at the University of Arizona. For simulations of the entire wing section we are using a high-order-accurate finite volume code based on the compressible NavierStokes equations. For very highly resolved DNS which focus exclusively on the separated region on the suction side of the wing, we are employing a higher-orderaccurate compact finite difference code based on the incompressible Navier-Stokes equations in vorticityvelocity formulation. These simulations are set up to fully resolve the flow field and enable us to reveal some of the intricate physical mechanisms associated with unsteady separation and transition, flow instabilities, and active flow control.

“…Two-dimensional (2-D) wing sections were tested in the wind and water tunnel for Reynolds numbers between 64,200 and Re=322,000, the model (1/5 scale) cruise Reynolds number based on Mean Aerodynamic Chord (MAC). [6][7][8] The experiments were complemented by simulations for Re=64,200,9,10 Re=322,000, 11,12 and Re=1 Million. 13 The full-size cruise Reynolds number is 3.2 Million.…”

Section: Introductionmentioning

confidence: 99%

Numerical Investigation of Separation Control for Wing Section at Re=300,000

43rd Fluid Dynamics Conference

Fasel

2013

Self Cite

Active flow control by harmonic blowing through a slot is investigated for a modified NACA643-618 airfoil at a chord Reynolds number of Re=300,000 and for 15 degrees angle of attack. A direct simulation of the uncontrolled flow serves as a reference for hybrid simulations using a one-equation renormalization group turbulence model. Because of their lower computational expense, two-dimensional hybrid calculations are employed for active flow control parameter studies. Downstream harmonic blowing through a spanwise slot is investigated. For a blowing ratio of 0.1 the control is ineffective. For blowing ratios and dimensionless forcing frequencies between one and two the actuation results in vortex shedding of the separated boundary layer and a moderate rise in lift.