Simulation Of The Single Compartment Fire By Using A Multi-layer Zone Model

The widely used two-layer zone model is easy to understand and can save calculating time. However, because the fire compartment is only divided into two layers vertically, the model can not provide detailed information in vertical direction for analysis of the fire, such the temperature and smoke concentration. Therefore in this paper, we divide the fire compartment into a lot of layers, based on the fact that there are temperature and smoke concentration gradients along the vertical direction in a fire compartment. Under the assumption of the constant temperature, pressure, smoke concentration within each layer and by using conservation of mass, energy, components and the state equation of the ideal gas, a multi-layer zone model is introduced. At the same time, to enclosure the multi-layer zone model, a lot of sub-model, including heat release model, smoke release model, flow model through opening, heat transfer model, are discussed and suggested. Three pieces of independent quantity are coupled mutually to pass to indoor temperature, pressure, and density in order to simulate the temperature and the smoke concentration more accurately.Based on the multi-layer zone model, a numerical model is developed. Under the use of the developed numerical model, the temperature and smoke movement in a single fire compartment is calculated and analyzed. The calculation is also compared the experimental data by Steckler and shown a good agreement of the calculation results with the experiments. This is indicated that the multi-layer zone model is reasonable.In addition, the numerical model is integrated into a visual tool with friend GUI, which is developed under Matlab6.5. The visual tool provides pre-processing and post-processing module. The pre-processing module can gather building geometry data, and set put the numerical model easily, while the post-processing module gives more possibilities to analyze the data produced by the numerical model. This will make the fire analysis more effective.