Estimates of the Uncertainty of Radiative Heat Flux Calculated From Total Heat Flux Measurements.
Estimates of the Uncertainty of Radiative Heat Flux
Calculated From Total Heat Flux Measurements.
Bryant, R. A.; Johnsson, E. L.; Ohlemiller, T. J.;
Womeldorf, C. A.
NIST SP 971; August 2001.
NIST SP 971: "Collected Reports and Publications by the
National Institute of Standards and Technology on Heat
Flux Gage Calibration and Usage." AND Interscience
Communications Ltd.; Building Research Establishment;
National Fire Protection Association; National Institute
of Standards and Technology; Society of Fire Protection
Engineers; and Swedish National Testing and Research
Institute. Interflam '2001. International Interflam
Conference, 9th Proceedings. Volume 1. September 17-19,
2001, Edinburgh, Scotland, Interscience Communications
Ltd., London, England, 605-616 pp, 2001.
Available from:For More Information on NIST SP 971 visit: WEBSITE:
ON BOOK SHELF: TH9112.I57 2001
heat flux; uncertainty; room fires; corner tests; fire
tests; radiative flux; thermal radiation; thermopiles
As part of an effort to characterize the uncertainties
associated with heat flux measurements in a fire
environment, an uncertainty analysis example was
performed using measurement data from a room corner
surface products test that followed the guidelines of
ISO 9705. Equations to model the heat transfer at the
surface of a Schmidt-Boelter (thermopile) type total
heat flux gauge were selected for use to calculate the
incident radiative flux from a total heat flux
measurement. The effects of the possible heat flux
measurement uncertainty sources were evaluated by
employing an uncertainty propagation on the resulting
equation for incident radiation. For the model equations
and the example conditions selected, the free-stream
temperature measurement and the heat flux gauge
calibration constant were suggested as major uncertainty
contributors. The study demonstrates how to
systematically identify major sources of uncertainty for
the purpose of reducing total uncertainty and therefore
enhancing experiment design.