Thermal conductivity measurements at and near room temperature are presented as the basis for certified values of thermal conductivity for SRM 1450d, Fibrous Glass Board. The measurements have been conducted in accordance with a randomized full factorial experimental design with two variables, bulk density and temperature, using the NIST 1016 mm line-heat-source guarded-hot-plate apparatus. The thermal conductivity of the SRM specimens was measured over a range of bulk densities from 114 kg∙m-3 to 124 kg∙m-3 and mean temperatures from 280 K to 340 K. Uncertainties of the measurements, consistent in format with current international guidelines, have been prepared. Statistical analyses of the physical properties from the SRM are presented and include variations between boards, as well as within board. Each unit of SRM 1450d is individually certified for bulk density, ρ, and batch certified for thermal conductivity with the following equation: λ=(1.10489x10-4)xTm where λ is the predicted thermal conductivity (W∙m-1∙K-1) and Tm is the mean temperature (K) valid over the temperature range of 280 K to 340 K. The expanded uncertainty for λ values from the above equation is 1% with a coverage factor of approximately k = 2.
Citation: Special Publication (NIST SP) - 260-173Report Number:
NIST Pub Series: Special Publication (NIST SP)
Pub Type: NIST Pubs
calibration, bulk density, fibrous glass board, guarded hot plate, heat flow meter, standard reference material, SRM 1450, thermal conductivity, thermal insulation, uncertainty