1. Institute of Public Safety Research, Department of Engineering Physics, Tsinghua University, Beijing 100084, China; 2. Xinjiang Vital Development and Construction (Group) Co., Ltd., Urumqi 830000, China
Abstract:Full-scale fire experiments in real highway tunnels were conducted to evaluate the temperature measurement errors in such experiments.The longitudinal temperature distributions in the tunnel were measured in repeated trials with the same conditions.Statistical analyses were then use to quantify the temperature measurement errors in different areas and at different times.The maximum error was more than ±20℃ with the maximum relative error reaching 40%.Fluctuations in the flow rate and fire power were two important factors affecting the uncertainties with then increased the standard deviation of the temperature in the smoke front arrival stage and the fire power attenuation stage.There were significant differences in the standard deviations of the temperature upstream and downstream of the fire source.The upwind smoke diffusion is more easily disturbed by flow rate fluctuations with a maximum relative temperature error of more than 20%.The results support accuracy evaluations and error analyses of full-scale experimental tunnel fire data.
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