Guide to Characterizing Heat Release Rate Measurement Uncertainty for Full-Scale Fire Tests.
Guide to Characterizing Heat Release Rate Measurement
Uncertainty for Full-Scale Fire Tests.
Bryant, R. A.; Mulholland, G. W.
Fire and Materials, Vol. 32, No. 3, 121-139, April/May
large scale fire tests; heat relese rate; uncertainty;
oxygen consumption; fire tests; fire safety; equations;
calorimetry; experiments; natural gas; temeprature
Accurate heat release rate measurements provide
essential information to defining the fire safety
characteristics of products. The size, complexity, and
cost of full-scale fire tests make achieving accurate
and quantitative results a serious challenge. A detailed
uncertainty analysis of a large-scale heat release rate
measurement facility is presented as a guide to the
process of estimating the uncertainty of similar
facilities. Quantitative heat release rate measurements
of full-scale fires up to 2.7 MW were conducted using
the principle of oxygen consumption calorimetry.
Uncertainty estimates were also computed for the heat
input measurements from a well-controlled natural gas
burner. The measurements of heat input and heat release
rate were performed independently, and the discrepancy
between the two was well within the uncertainty limits.
The propagation of uncertainty was performed at the
level of voltage and temperature measurements, which
avoided using mutually dependent measurement parameters.
Reasons for the significant contribution to the combined
uncertainty from the oxygen concentration and exhaust
flow measurements are demonstrated. Also presented is a
first-order effort to account for the uncertainty due to
factors in full-scale fire tests such as operator error
and environmental influences that are not modeled by the
heat release rate equation.