Improved NIST Airspeed Calibration Facility

Published

March 23, 2010

Author(s)

Iosif I. Shinder, J. M. Hall, Michael R. Moldover

Abstract

The National Institute of Standards and Technology (NIST) uses a laser Doppler anemometer (LDA) as a working standard for airspeed calibrations in the range 0.15 m/s to 75 m/s (0.34 to 168 miles/hour). We report improved procedures for calibrating the LDA that reduced its uncertainty from 0.26% to 0.10% at airspeeds above 1 m/s. (Uncertainties are stated with the coverage factor k=2 which corresponds to a 95 % confidence level.) The calibration uses a rotating disk with known dimensions at several known rotation frequencies, thereby tracing the LDA to the primary standards of length and time. We also improved the LDA signal-to-noise ratio in NIST’s wind tunnel, particularly at higher air speeds, by replacing a water seeding system with an oil seeding system. New software automates the airspeed setting, oil-seeding rate, data-collection time, and instrument averaging time.

Proceedings Title

Measurement Science Conference Proceedings

Conference Dates

March 22-26, 2010

Conference Location

Pasadena, CA

Pub Type

Conferences

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Keywords

atomizers, airspeed calibrations, laser Doppler anemometer, primary standards

Citation

Shinder, I. , Hall, J. and Moldover, M. (2010), Improved NIST Airspeed Calibration Facility, Measurement Science Conference Proceedings, Pasadena, CA, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=904871 (Accessed April 18, 2024)