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Accession Number N20120014596
Title Using Indirect Turbulence Measurements for Real-Time Parameter Estimation in Turbulent Air.
Publication Date Aug 2012
Media Count 29p
Personal Author B. Martos E. A. Morelli
Abstract The use of indirect turbulence measurements for real-time estimation of parameters in a linear longitudinal dynamics model in atmospheric turbulence was studied. It is shown that measuring the atmospheric turbulence makes it possible to treat the turbulence as a measured explanatory variable in the parameter estimation problem. Commercial off-the-shelf sensors were researched and evaluated, then compared to air data booms. Sources of colored noise in the explanatory variables resulting from typical turbulence measurement techniques were identified and studied. A major source of colored noise in the explanatory variables was identified as frequency dependent upwash and time delay. The resulting upwash and time delay corrections were analyzed and compared to previous time shift dynamic modeling research. Simulation data as well as flight test data in atmospheric turbulence were used to verify the time delay behavior. Recommendations are given for follow on flight research and instrumentation.
Keywords Atmospheric turbulence
Correction
Dynamic models
Flight tests
Flow measurement
Parameter identification
Real time operation
Time lag
Turbulent flow
Upwash


 
Source Agency National Aeronautics and Space Administration
NTIS Subject Category 51A - Aerodynamics
51B - Aeronautics
55B - Dynamic Meteorology
Corporate Author National Aeronautics and Space Administration, Hampton, VA. Langley Research Center.
Document Type Conference proceedings
Title Note N/A
NTIS Issue Number 1308
Contract Number N/A

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