Fire exposure measurements using plate thermometers

Abstract

AbstractPlate thermometers (PT) are known and utilized in fire testing for more than 30 years. They are simple devices that measure the temperature of the thin plate, made of a thermal conductor, that is exposed to fire from one side and insulated from the opposite side. The main advantage of measuring thermal exposure using a plate thermometer is its ability to capture both the convective and radiative parts of the heat flux. However, thermal exposure is not directly the value the plate thermometer outputs. For this reason, an adiabatic surface temperature (AST), which could be considered as an objective measure of thermal exposure, can be calculated on the basis of the plate thermometer output. In this work, the abilities for fire‐exposure measurements using plate thermometers are discussed.This work introduces the closed‐form analytical solution of the plate thermometer heat balance equation for an adiabatic surface temperature. The authors consider the introduced solution as the best method, at this moment, for the evaluation of AST based on the PT output. This allows several findings to be presented that are not affected by the shortcomings of previously used methods for the AST evaluation.