STP1427: Calibration of a Heat Flux Sensor up to 200 kW/m2 in a Spherical Blackbody Cavity

    Murthy, AV
    President, Aero-Tech, Inc., Hampton, VA

    Tsai, BK
    Physical Scientist, Optical Technology Division, NIST, Gaithersburg, MD

    Saunders, RD
    President, Saunders Enterprises, Gaithersburg, MD

    Pages: 16    Published: Jan 2003


    Abstract

    This paper presents the results of a comparative study of narrow view-angle and wide view-angle calibrations of a water-cooled Schmidt-Boelter heat-flux sensor. The narrow view-angle calibration, up to a heat flux level of 50 kW/m2, was conducted using the 25 mm Variable Temperature Blackbody (VTBB) facility. An electrical substitution standard was used as a transfer standard to determine the flux level at the sensor plane. The wide view-angle calibration was conducted by placing the sensor inside the radiating cavity of a spherical blackbody. The calibration in the spherical blackbody is based on the heat-flux derived from the Stefan-Boltzmann equation using the blackbody temperature measured from a type-S thermocouple. The calibration covered an extended range from 50 kW/m2 to 200 kW/m2. Results of the calibration of the heat-flux sensor using the two different techniques are presented. A discussion of the problems associated with calibrating sensors at high heat-flux levels by inserting the sensor inside a blackbody cavity is also presented.

    Keywords:

    blackbodies, heat-flux, sensors, thermal radiation, transfer calibration


    Paper ID: STP10948S

    Committee/Subcommittee: E05.13

    DOI: 10.1520/STP10948S


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