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Opportunity at Air Force Research Laboratory (AFRL)

Aero-Effects for High Energy Laser Systems, Experiments and Computations

Location

Directed Energy Directorate, RD/Physical Sciences

RO# Location
13.10.02.C0050 Kirtland Air Force Base, NM 871175776

Advisers

Name E-mail Phone
Wittich, Donald Joseph donald.wittich.1@us.af.mil 505-846-5071

Description

"Aero-effects" research seeks to understand and mitigate aerodynamic effects on aircraft-mounted optical systems. These effects include: aero-optics, the process by which aerodynamic turbulence distorts light passing through it, and aero-mechanical jitter, a form of fluid-structure interaction.

Experimental aero-effects research includes wind-tunnel and flight testing to characterize turbulence in compressible flows of interest (e.g., the three-dimensional flow around an aircraft-mounted optical turret) as well as canonical configurations (e.g, turbulent boundary layers and mixing layers). This research includes opportunities to develop and apply modern flow-diagnostic techniques (e.g, Particle-Image-Velocimetry, Laser-Induced-Fluorescence, Pressure-Sensitive-Paint, Background-Oriented-Schlieren, wavefront sensing, etc.) to quantify and understand aero-optical phenomena and predict aero-mechanical jitter.

Computational aero-effects research uses CFD methods from Euler codes up to Large-Eddy Simulations to quantify and understand aero-optical phenomena and predict aero-mechanical jitter. Researchers will have the opportunity to model flow-field turbulence in increasingly complex configurations with the ultimate goal of modeling the aero-effects associated with full-scale flight systems. The computational and experimental research paths both include opportunities to apply and expand spatio-temporal analysis techniques which relate the fluid-dynamics to aero-effects (e.g. Fourier analysis, Proper-Orthogonal-Decomposition, Linear-Stochastic Estimation, etc.). Overall research objectives include: (1) anchoring high-fidelity computational simulations, (2) accurately quantifying aero-optical and aero-mechanical disturbances, and (3) developing and demonstrating technical solutions to mitigate the aero-effects.

 

References

Gordeyev S, De Lucca N, Jumper E, Hird K, Juliano TJ, Gregory JW, Thordahl J, Wittich DJ: “Comparison of Unsteady Pressure Fields on Turrets with Different Surface Features using Pressure Sensitive Paint”. Experiments in Fluids 55: 1661, 2014

Mani A, Gordeyev S: “Physics and computation of aero-optics“. Annual Review of Fluid Mechanics 44: 299-321, 2012

Goorskey DJ, Drye R, Whiteley MR: “Dynamic modal analysis of transonic Airborne Aero-Optics Laboratory conformal window flight-test aero-optics”, Optical Engineering 52(7): 071414, July 2013

 

Keywords:
Fluid-dynamics; Aero-optics; Flow-control; Flow-diagnostics; Turbulence; Lasers; Beam-control; Aero-effects; CFD;

Eligibility

Citizenship:  Open to U.S. citizens
Level:  Open to Postdoctoral and Senior applicants
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