Control Stability of a Heat-Flow-Meter Apparatus.
Control Stability of a Heat-Flow-Meter Apparatus.
(327 K)
Zarr, R. R.
American Society for Testing and Materials. Measurement
Errors and Methods of Calibration of Heat-Flow-Meter
Apparatus. ASTM C-16 Workshop. April 9, 1994,
Williamsburg, VA, 1994.
Journal of Thermal Insulation and Building Environments,
Vol. 18, 116-127, October 1994.
Keywords:
building technology; heat flow meter; control stability;
fibrous glass; heat transmission; steady state
Abstract:
Calibration measurements of a commercial heat-flow-meter
apparatus are presented. The apparatus has been
calibrated using the same specimen of high-density
fibrous-glass board over a period of four years, from
1989 to 1993. A total of seventy-three tests have been
conducted generally, at ambient conditions of 24 deg C
with a moderate temperature difference of either 15, 22
or 27 deg C across the specimen. Variations within a
set of data for each test have been examined to verify
underlying assumptions of randomness, normal frequency
distribution of errors, repeatability, and stability of
the data. Variations between test data indicate a small
drift, on the order of one percent over four years, in
the calibration factor of the apparatus. A model has
been developed to describe the small drift with time.
The analysis of variations between test data has also
identified intermittent shifts in the precision of the
calibration factor of the apparatus.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899