Last modified: 2017-07-13
Abstract
The fire resistance of the construction materials is traditionally measured by the fire resistance test method in accordance with the international standards, i.e. ISO 834-1, BS476-20, and ASTM E119, etc. In fire resistance door test, a full-scale test door is fitted into a standardized furnace for testing and then the test report is issued to ensure how long the door can resist the fire. Test report relates only to what has been tested. To verify the fire resistance performance, changes to a construction or components on the original tested system require either another fire test or an assessment method. Traditionally, the assessment method is depending on the tested reports and the accessor’s experience. In a scientific point of view, an accurate heat transfer model can help the door designer and accessor to evaluate the fire resistance performance if any changes on the original tested door. Therefore, this study is to apply the CFD method to analyze the heat transfer through a fire door tested under a standardized time-temperature curve.
A single leaf wooden door was tested in this study. During the 1-hour test, the temperatures inside the furnace and six measured points on the unexposed surface were recorded with the thermocouples. The commercial CFD software, COMSOL Multiphysics®, was used to develop a three-dimensional heat transfer model of the fire door under the fire resistance test. In results, it showed that the curve trends of the simulated unexposed temperature of the six measured points generally agreed with the experimental data. For the door leaf, the maximum temperature error between the experimental data and the simulated data was within ± 20%. For the door frame, the maximum temperature error between the experimental data and the simulated data was within ± 30%. The larger difference on the frame was calculated because the practical smoke passing through the door gap between the leaf and frame, due to the door sealant failure, was not simulated in this model.