A past investigation of the flow of hot gases in roof venting led to the development of a simple zone model which for many years has formed the basis for the design of practical roof venting systems. Although calculations of equilibrium depths of the layer of hot gases agree with the results of large-scale experiments, there were no large-scale experiments against which calculations of increase in depth with time could be validated. Recent experiments of Yamana and Tanaka have provided such data and in this paper their results are compared with the predictions of the original model. Calculations have also been made for situations where Yamana and Tanaka did not calculate the increase in depth with time. The correlation is at least as good as that provided by the more recent model of Tanaka and Yamana. There is some evidence that when the layer of hot gases had fallen to within 3 m of the floor of the unvented compartment smoke-logging followed rapidly. This is not predicted by simple models.

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Heat flux out of a burning wooden house was studied. In a full scale fire experiment of a three story wooden house, which was recently executed in Tokyo, Temperature of heat source was examined using a thermal camera. Data was converted to heat emission rate and for the validation of the conversion method, the data was compared to radiation data measured by conventional flux gauges. In another experiment and heat emission from different portions of building facade was studied. This paper is a revised version of ref. ^[1]

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A field equation model was developed for the interaction analysis of turbulent natural convection and radiation in the 'pre-flashover' compartment fire. Radiation in non-gray gases and soot mixtures was analyzed by a differential approximation method. A κ - ε model for turbulent flow was considered. The Favre (mass) averaged governing equation system was solved by an efficient iterative method incorporating a multi-dimensional simultaneous finite difference equations solver. Computations were performed on a two-dimensional room-corridor system with a localized fire source in the room. Effects of radiation on the flow and temperature fields have been identified. Soot radiation significantly altered local characteristics of the temperature field.

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