Application of symbolic mathematics in modelling fire for providing a safe environment

摘要

Symbolic mathematics should be a good tool for fire hazard assessment in performance-based design. Fire environment can be predicted interactively in a personal computer. The concept is further demonstrated in this paper by taking the model FIRM as an example. This is a two-layer zone model upgraded from an earlier model ASET, but allowed to have a vertical opening. In this way, the two key equations on smoke layer temperature and interface height are much more difficult to solve, on comparing with ASET. The five ventilation conditions identified across the vertical opening are highlighted. The two key equations are solved by symbolic mathematical package. Predictions are compared with experimental data on systematic room fire studies reported by National Institute of Standards and Technology, USA; and local studies on full-scale burning tests on smoke filling in an atrium fire and indoor thermal environment induced by an electric heater in a fire laboratory. Results are also compared with well-developed zone models. All these demonstrate the beauty of symbolic mathematics for modelling fire in projects requiring performance-based design. Such symbolic calculation is able to solve complicated fire problems with interactive technical documents.