It is often necessary to prevent fire spread between certain areas, such as adjacent buildings. This can have implications on the amount of unprotected façade that can be permitted for buildings (to prevent fire spread to an adjacent building) or in other areas such as preventing fire spread between kiosks in shopping centres.
The calculation of radiative heat transfer between two surfaces is computationally intensive because it relies on the three-dimensional geometrical relationship between the two surfaces. Standard methods of analysis of this (such as the ‘Enclosing Rectangles’ method) therefore simplify the calculation into a tabular method. Within their range of application these methods therefore give good results, but they are inflexible, and when there is an unusual situation or complicated façade, the results will tend to be over-conservative.
Maze Fire Consulting has therefore developed an in-house computer program (MZ Rad) that can be used to calculate radiation between many surfaces. These therefore allow analysis of a wide range of geometrical configurations without requiring the over-conservative approach achieved by other methods.
In certain situations, this can give a significant advantage over other, more traditional methods, permitting larger amounts of unprotected façade than would otherwise be achieved.
Figure 1: Typical output from MZ Rad computer model
Figure 2: Typical output from MZ Rad computer model