Estimating temperatures in compartment fires

Abstract

Models to calculate the fire temperature for compartments are of great importance when designing fire protection in buildings, both to save lives and to save money. There are a range of models that are good at estimating the fire temperatures for compartments with surrounding structures made of concrete, brick, wood and other similar building materials. However, there are very few simple models for compartments with thermally thin surrounding structures, with- or without insulation. The purpose with this report is to show that it is possible to calculate the fire temperature within different types surrounding structures with simplemodels. The purpose is also to present the results in a pedagogical way. This report presents simple models for semi-infinite surrounding structures and thermally thin surrounding structures with- or without insulation. These models have been derived in similar ways and indicate which parameters that affect the fire temperature development. A numerical solution for thermally thin surrounding structures has also been developed. These solutions are presented in an Excel spreadsheet that allows the user to change parameters input. The new model for semi-infinite surrounding structures results in a similar fire temperature curve as the parametric fire curve according to EUROCODE 1 and the ISO-834 curve. The new model for thermally thin surrounding structures with- or without insulation results in fire temperatures that match experimentally measured fire temperatures. Even though the new model gave good results, there are still a few things that need to be improved. More research on the different parameters used in the model, especially the combustion efficiency, is needed to set the right values for each parameter. The model should be compared with more varying experiments to conclude its limits and to validate the model.