- Author
- Zarr, R. R. | Licitra, B. A.
- Title
- Calibration at 24°C of a Heat-Flow-Meter Apparatus Having 610 mm Square Plates.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD
- Sponsor
- Department of Energy, Washington, DC
- Report
- NISTIR 4539, May 1991, 35 p.
- Distribution
- Available from National Technical Information Service
- Keywords
- calibration | computer | data-acquisition-system | guarded hot plate | heat-flow-meter | heat-flux-transducer | Standard Reference Materials | thermal conductivity
- Abstract
- Results are summarized for 38 individual calibration measurements conducted at 24 deg C and atmospheric conditions for a heat-flow-meter apparatus having 610 mm square plates. The apparatus was calibrated using a 26.2-mm-thick specimen of fibrous-glass board having a density of 139 kg/m3. The specimen was selected from an internal log (Lot 1970) of Standard Reference Material (SRM) similar to SRMs 1450, 1450a, and 1450b. Values of apparent thermal conductivity were predicted using a regression equation developed for this lot of fibrous-glass insulation. Calibration measurements varied ±0.4% with a small drift of 0.4% over 250 days. The apparent thermal conductivity of the calibration specimen was also measured using the National Institute of Standards and Technology's one-metre Line-Heat-Source Guarded Hot Plate. Agreement between measurements of thermal conductivity of the guarded hot plate and predicted values were within +0.2 to -0.3% at 24 deg C. The report describes the heat-flow-meter apparatus and the computer data-acquistion-system used to collect data from the apparatus.