CFAST在大空间火灾模拟中的应用研究

为了实现区域模拟软件CFAST在大空间火灾模拟中的应用,深入研究多区域模拟的模拟效果,引入了均匀划分和局部加密的两种多区域模拟方法.采用与实验研究相结合的方法,与测量结果对比,发现采用均匀区域划分方法时,在满足CFAST允许的区域总数要求和每个区域符合CFAST推荐的区域尺寸比例的条件下,采用的区域越多,模拟结果越精确；同时,采用在火源附近区域分布密集的局部加密划分方法,模拟效果优于均匀划分方法,烟气层最高温度相对实验测量结果的误差仅为4.3％,更接近实际.

Application of CFAST in fire simulation of large scale buildings

In order to realize the application of CFAST in fire simulation of large scale buildings,the cell-zone method was taken to analyze the simulation performance.Two kinds of cell-zone method were discussed,which were a large scale building being divided into spaces in uniform form and the way of partial improvement of spaces density.Experiment was done in a real large scale building.The research was combined with theoretical analysis,and the measured data was compared with the simulation result.It was found that the number of the zones adopted was in proportion to the accuracy of simulation result on conditions that the size of each cell-zone was recommended in CFAST and the total number was less than 30,which was the maximum of the zones allowed in CFAST.At the same time,another conclusion was also derived that the way of partial improvement of spaces density around the fire was superior to the division in uniform form through the comparison of smoke temperature and the phenomenon.The relative error between the smoke temperature simulated in the former way and the experimental result was 4.3%,which indicated the former way approaches to the reality a lot and it was appropriate to simulate the fire of large scale building.