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Fluctuating pressures measured beneath a high-temperature, turbulent boundary layer on a flat plate at Mach number of 5Fluctuating pressures were measured beneath a Mach 5, turbulent boundary layer on a flat plate with an array of piezoresistive sensors. The data were obtained with a digital signal acquisition system during a test run of 4 seconds. Data sampling rate was such that frequency analysis up to 62.5 kHz could be performed. To assess in situ frequency response of the sensors, a specially designed waveguide calibration system was employed to measure transfer functions of all sensors and related instrumentation. Pressure time histories were approximated well by a Gaussian prohibiting distribution. Pressure spectra were very repeatable over the array span of 76 mm. Total rms pressures ranged from 0.0017 to 0.0046 of the freestream dynamic pressure. Streamwise, space-time correlations exhibited expected decaying behavior of a turbulence generated pressure field. Average convection speed was 0.87 of freestream velocity. The trendless behavior with sensor separation indicated possible systematic errors.
Document ID
19900001364
Acquisition Source
Legacy CDMS
Document Type
Technical Publication (TP)
Authors
Parrott, Tony L.
(PRC Kentron, Inc., Hampton VA., United States)
Jones, Michael G.
(Planning Research Corp. Hampton, VA., United States)
Albertson, Cindy W.
(NASA Langley Research Center Hampton, VA, United States)
Date Acquired
September 6, 2013
Publication Date
November 1, 1989
Subject Category
Acoustics
Report/Patent Number
NAS 1.60:2947
L-16596
NASA-TP-2947
Accession Number
90N10680
Funding Number(s)
PROJECT: RTOP 506-80-31-06
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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