However, conventional compartment fire models were developed for non-combustible construction. GoZone shows a promising capacity to represent fires in a large compartment in both air and fuel controlled fire conditions.Ĭross-laminated timber (CLT) is a mass timber product that has attracted increasing interest in mid- and high-rise building construction. A comparison is given with the results of under ventilated fire test 2 of the BST/FSR 1993 test series and with respect to the Veselì travelling fire test is shown. The main sub models comprising GoZone are presented. GoZone is aimed to describe the complex dynamics of the fire from ignition to a phase of growing localised fire that may eventually travel in the compartment, possibly followed by a flashover. The software GoZone, in which the model was implemented, is intended to be a practical solution to analyse fires in large compartments of potentially any shape. The model was based on an improved zone model combined with a cellular automata model. The purpose of this paper is to present a numerical model of travelling fire. Although these models represented an innovative step in the field of travelling fires, the major drawbacks of these models can be found in the simplification of fire dynamics (constant spread rate, 1D imposed fire path) and limited field of application (rectangular based geometries). Several models have been proposed to describe the evolution in time of travelling fires. Recent studies on fires in large compartments have led to the now widely known concept of “travelling fires”. A more in-depth discussion of the results is provided, with some ideas on the direction of further developments in fire testing.įires in large compartments tend to burn locally and to move across the floor over a period of time this particular behaviour has been discovered to challenge the assumption of uniform gas temperature in the fire compartment. In case of doors, it was observed that combustible samples required significantly less heat than the benchmark case (40%-70% less), which indicates that the combustion of the sample inside of the furnace was an additional, significant source of heat release, that may skew the qualitative assessment of their performance in fire. It was observed that walls built with highly insulated sandwich panels require less heat to maintain standard thermal exposure conditions (20%-30% less) than their counterparts built from gypsum plasterboard or aluminium and fire-rated glass. These assemblies were also compared with the results of the test of a wall built with aerated autoclaved concrete blocks that was considered as the benchmark test. The assemblies were subdivided into two groups-wall assemblies and fire-rated doors. A total of 379 tests of vertical assemblies was investigated, all performed in furnace SPARK of the ITB Fire Testing Laboratory, in 2015-2018. The paper aims to explain the differences found in the heat release rate measurements in a large sample of standard fire tests (EN 1363-1). The equation used to calculate the reduced near-field temperature due to flapping is shown below and is derived from Alpert's ceiling jet correlation. The newly calculated reduced nearfield temperature is used to generate travelling fire time-temperature curves instead of a fixed peak value of 1200˚C. This represents the mixing of cooler smoke with fluctuating flame resulting in a lower near-field temperature. Over this length the average temperature is calculated including both far-field and peak near-field temperatures (1200˚C). 1981) experiments.In this TFM the flapping angle as identified previously is used to calculate the ceiling length over which the impinging fire fluctuations occur. 2015) based on results from Quintiere et al. 2015) For the updated version of TFM the flapping angle of ☖.5º was chosen (Rackauskaite et al. Representation of the flapping length on the ceiling (Rackauskaite CC BY-ND) (left) and variation of reduced near-field temperature with flapping angle and fire size(right) (Rackauskaite et al.
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