Aerodynamics and Fluid Mechanics include the study of the overall aerodynamic properties of vehicles and the performance of air-breathing engines, rockets, propellers and rotors. The School of Aerospace Engineering is conducting cutting-edge research that leads to improved understanding of the detailed physical phenomena that control these flows.
Current research activities in the School of Aerospace Engineering span the flow speed range from incompressible flow studies of horizontal axis wind turbines used for electricity generation to hypersonic flow prediction of planetary entry vehicles. Research topics include: computational aeroacoustics, aerodynamics of highly maneuverable aircraft, measurement and computational prediction of rotary wing aerodynamics, sonic boom prediction and reduction methods, adaptive subgrid models for large-eddy simulation of turbulence, parallel and distributed computing algorithms, fluid flow imaging, diagnostics, and control, prediction of chemically reacting and thermally excited hypersonic flows, vortex interactions and vortex flow control, direct numerical simulation of turbulence on massively parallel computers, hypersonic propulsion/airframe integration, and turbulent mixing and radiative signatures from aircraft and rocket plumes.
Many interdisciplinary research projects, such as the Center for Excellence in Rotorcraft Technology (CERT) and the Multidisciplinary University Research Initiative on Intelligent Turbine Engines (MITE), rely heavily on aerodynamics and fluid mechanics studies. Collaborative research with the Aerospace Systems Design Lab (ASDL) are also conducted to improve full configuration designs of fixed-wing aircraft, rotorcraft, and spacecraft.
Experimental, computational, and theoretical approaches are used in the study of aerodynamics and fluid mechanics. State-of-the-art experimental facilities include the John J. Harper Wind Tunnel, which has a 7 x 9 foot test section and a speed range of 10 to 220 feet per second. A variety of vortex flow studies are being conducted in this facility, notably in twin-tail buffeting, forebody asymmetry control, and rotorcraft vortex interactions. A multiple-degree-of-freedom wind driven manipulator has been developed and is currently used to simulate dynamic maneuvers for model testing. Diagnostic capabilities include laser velocimetry, automated scanning of static pressure and condenser microphone sensors, hot-film anemometry, high-frequency pulsed laser sheet imaging, and digital signal and image processing. Additionally, a 42 x 42 inch aerocontrols wind tunnel is available for diagnostic development, flow control experimentation, and small scale testing.
The School’s 9 foot hover facility is a double-walled, double-celled,
rotor test chamber that is used as a testbed for rotor aerodynamics and
diagnostic developments. The aeroelastic rotor test chamber facility is
a state-of-the-art 16-foot hover facility where rotor blades can be subjected
to digitally-controlled higher-harmonic excitation using hydraulic actuators
on the pitch links.
Computational fluid dynamics has emerged as a powerful tool for predicting
aerodynamic performance and providing insight into complex fluid dynamic
phenomena. Methods for solving various forms of the unsteady, three-dimensional
Navier-Stokes equations are developed and applied to fluid flows. This
work relies on a wide range of computational facilities whose capabilities
are continually expanded. Moderately sized two- or three-dimensional numerical
simulations are conducted with over a dozen Silicon Graphics, IBM, and
Hewlett-Packard computational workstations, used for grid generation,
computation, post processing, and scientific visualization of flow fields.
More computationally intensive simulations are typically conducted in
the Heterogeneous Computing Environment for Parallel Processing (HCEPP)
Laboratory which consists of two Silicon Graphics Power Challenge computers.
The facility has 1.3 GB of RAM, and each of the two computers houses six
high speed processors. Large-eddy turbulent simulations (LES) and computational
grid intensive studies of full aircraft configurations are typically solved
in the HCEPP Laboratory. Computationally intensive simulations are also
conducted in Georgia Tech’s High Performance Parallel Computation
and Experimentation Laboratory (HPPCEL), and at remote supercomputing
sites. AE researchers are utilizing such facilities to conduct direct
numerical simulations employing as many as 100 million grid points to
understand and model turbulent flow physics. The HPPCEL is located at
Georgia Tech and includes a continuously upgraded suite of high speed,
multiprocessor computers. Georgia Tech is also currently establishing
a dedicated high performance computing network (HPCNet) which will link
various systems for distributed/virtual parallel supercomputing.