Study of the influence of convective effects in incident radiative heat flux density measurement uncertainty

Abstract

This study describes the measurement uncertainty propagation of the incident radiative heat flux density quantity associated with different exposure conditions of the heat flux meter, taking into account the convective effects in reaction to fire tests. To accomplish this aim, considering the complexity and non-linearity of the applied mathematical models to perform the indirect measurement of the mentioned quantity, the Monte Carlo method approach was selected. The use of this numerical approach allows to determine the quality of the measurements within a high accuracy level and to overcome the main constrains found in other methods, specially the GUM method, which can only provide an approximate solution for this metrological problem. The experimental examples studied concern the reaction to fire testing (the room-corner test and the flooring radiant panel test) with different exposure conditions of the heat flux meter used. For each case, the applied mathematical model is described and an analysis of the input uncertainty contributions is presented