Fire Safety Science Digital Archive

Even though considerable work has been performed regarding gas temperatures and burning rates in enclosures, scant information is available for the heat fluxes and their distributions on the walls of an enclosure. These heat fluxes are necessary input for determining the thermal response and performance of the wall materials and especially glazing. The heat fluxes on the wall of an experimental enclosure were deduced from the temperatures in several thermally thin small steel plates (25.4 mm x 25.4 mm x 3 mm thick) and in the insulation surrounding the steel plates. In addition, the mass loss rate and gas temperatures near these heat flux gauges were measured. The experimental enclosure was the 1/3 linear scale of the ISO room corner test having six openings and three square- pans of variable size burning Methanol, IMS (Industrial Methylated Spirits) and Toluene at the corner and in the center of the enclosure. By choosing fuels with an increased degree of sootiness it was found that the heat fluxes do not depend only on the gas temperature, as claimed before for heat fluxes on the floor, but also on the magnitude of the heat release rate and the fuel sootiness. Moreover, comparison of the heat fluxes for methanol, IMS and toluene allow the separation of convective from radiative heat fluxes owing to hot gases (and the enclosure walls) and from the radiative heat fluxes from the fire plume.