基于ISO9705房间木垛火试验的FDS模拟预测研究

Research on the prediction of FDS simulation based on the ISO 9705 room wood crib fire test

为了验证FDS模拟的有效性和可靠性,在ISO 9705试验房间内进行一定荷载的木垛火试验。利用火灾动力学模拟软件FDS针对同样的火灾场景进行模拟计算,比较不同网格配置对模拟结果的影响。结果表明:Multi-block格点配置是最佳的格点配置形式,其模拟得到的木垛火热释放速率变化、烟气温度变化、CO2体积分数变化的结果能够很好地与实测值吻合,但对CO体积分数不能准确模拟;Multi-block能够在不降低计算精度的前提下,降低格点数目,减少计算时间,节约计算成本。

The objective of this article is to validate the effectivity and reliability of FDS （Fire Dynamics Simulator） , for this purpose ,crib fire at some fire load was carried in the ISO 9705 room, meanwhile the same fire scenario was simulated by means of FDS, three types of grid including uniform grid size, non-uniform grid size and Multi-block grid size analysis were used in the process of simulation. And the simulated results were compared aimed at the influence of grid size to the simulation results, and similarity of FDS simulation with the experiment results from the aspects of HRR, hot smoke temperature and smoke concentration . The best type of grid distribution was determined in the end. The result shows that the Multi-block grid distribution is the best type. Under this condition, the HRR,temperature profile of the smoke and the concentration of carbon dioxide simulated by the FDS agree well with the measure value tested in the crib fire, but the concentration of carbon monoxide could not be simulated accurately. Multi-block grid distribution could decrease grid number, reduce competing time and save the computing cost on the premise that the precision of computing could not be reduced.