NASA Scientific and Technical Aerospace Reports

20040120985 NASA Langley Research Center, Hampton, VA, USA
Generic Hypersonic Inlet Module Analysis
Cockrell, Chares E., Jr.; Huebner, Lawrence D.; [2004]; 12 pp.; In English; AIAA 9th Applied Aerodynamics Conference,
24-26 Sep. 1991, Baltimore, MD, USA
Report No.(s): AIAA Paper 91-3209; Copyright; Avail: CASI; A03, Hardcopy
A computational study associated with an internal inlet drag analysis was performed for a generic hypersonic inlet
module. The purpose of this study was to determine the feasibility of computing the internal drag force for a generic scramjet
engine module using computational methods. The computational study consisted of obtaining two-dimensional (2D) and
three-dimensional (3D) computational fluid dynamics (CFD) solutions using the Euler and parabolized Navier-Stokes (PNS)
equations. The solution accuracy was assessed by comparisons with experimental pitot pressure data. The CFD analysis
indicates that the 3D PNS solutions show the best agreement with experimental pitot pressure data. The internal inlet drag
analysis consisted of obtaining drag force predictions based on experimental data and 3D CFD solutions. A comparative
assessment of each of the drag prediction methods is made and the sensitivity of CFD drag values to computational procedures
is documented. The analysis indicates that the CFD drag predictions are highly sensitive to the computational procedure used.
Author
Computational Fluid Dynamics; Computation; Hypersonic Inlets; Intake Systems
08
AIRCRAFT STABILITY AND CONTROL
Includes flight dynamics, aircraft handling qualities, piloting, flight controls, and autopilots. For related information see also 05 Aircraft
Design, Testing and Performance and 06 Avionics and Aircraft Instrumentation.
20040111476 Georgia Inst. of Tech., Atlanta, GA
Neural Network Based Adaptive Control of Uncertain and Unknown Nonlinear Systems
Calise, Anthony J.; Mar. 31, 2004; 18 pp.; In English
Contract(s)/Grant(s): F49620-01-1-0024
Report No.(s): AD-A425419; AFRL-SR-AR-TR-04-0416; No Copyright; Avail: CASI; A03, Hardcopy
The objectives of this research effort were to exploit recent advances in neural network (NN) based adaptive control, with
the goal of being able to treat a very general class of nonlinear system, for which the dynamics are not only uncertain, but
may in fact be unknown except for minimal structural information, such as the relative degree of the regulated output
variables. We were particularly interested in designing adaptive control systems that are robust with respect to both parametric
uncertainty and unmodeled dynamics. Extensions to decentralized control were also of interest. In addition, we placed a high
priority on transition opportunities in aircraft flight control, control of flows, control of flexible space structures, and control
of aeroelastic wings.
DTIC
Adaptive Control; Network Control; Neural Nets; Nonlinear Systems; Uncertain Systems
20040111756 Micro Analysis and Design, Boulder, CO
Multisensory Integration for Pilot Spatial orientation (MIPSO)
Small, Ronald L.; Wickens, Christopher D.; Oster, Alla M.; Keller, John W.; French, Jon W.; Mar. 2004; 103 pp.; In English
Contract(s)/Grant(s): F33615-03-M-6360; Proj-3005
Report No.(s): AD-A425966; AFRL-HE-WP-TR-2004-0035; No Copyright; Avail: CASI; A06, Hardcopy
Spatial disorientation (SD) is a normal human response to accelerations in flight, and has existed since early flight. Its cost
to the US military is over $300 million per year, with comparable costs to US civil aviation. Despite significantly increased
research over the past decade, the rate of accidents caused by SD has not decreased. While the most recent research emphases
have been on understanding the physiology of SD, the translation of the new knowledge into tools (e.g., training, displays,
automation) that help pilots avoid SD and minimize its effects if it does occur, has not occurred. The goals of the research
reported here were to apply multisensory countermeasures to SD based on human sensory models and the pilot’s workload.
It is the premise of this Phase I effort that more effective multisensory countermeasures, applied in an intelligent fashion, are
needed and possible, and that modeling and simulation are the most cost effective means to identity and test countermeasures
for different aircraft under varying conditions.
DTIC
Attitude (Inclination); Countermeasures; Disorientation; Navigation Aids; Physiology
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