Large-eddy simulation of the plume generated by the fire at the Buncefield oil depot in December 2005
Large-eddy simulation of the plume generated by the fire at the Buncefield oil depot in December 2005
复制标题
2005 年 12 月邦斯菲尔德油库火灾产生羽流的大涡模拟
DOI：
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发表时间：
2009
期刊：
影响因子：
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通讯作者：
J. Edwards
中科院分区：
文献类型：
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作者：
B. Devenish;J. Edwards
2005年12月11日，英国赫特福德郡邦斯菲尔德油库发生爆炸，引发了二战以来欧洲最严重的火灾。因此，火灾的强度和产生的羽流的规模对任何浮力羽流的数学模型都提出了严格的考验。具有适当初始条件的 Boussinesq 方程的大涡模拟可以重现所观察到的羽流的特征；羽流在源头上方的高度和顺风传播的方向都与观测结果相符。这支持了布辛涅斯克假设的使用，即使对于邦斯菲尔德火灾产生的如此强大的羽流也是如此。真实水蒸气剖面的存在不会导致羽流的显着额外潜热，但由于水蒸气提供的浮力增加而导致羽流最终上升高度的小幅增加。我们的模拟包括辐射与羽流中气溶胶的相互作用，并重现观察到的羽流光学厚度和到达地面的太阳辐射的减少。在远离源头的下风处，太阳辐射在横向扩散的羽流中发挥着作用，但其作用方式取决于气溶胶浓度。在气溶胶浓度高的情况下，羽流的厚度增加；入射的太阳辐射在如此小的深度上被吸收，以至于只有羽流的顶部向上翘起，并且相对于没有辐射的情况，最大浓度水平几乎保持不变。当气溶胶浓度较低时，整个羽流被入射的太阳辐射加热，并且放样更加连贯，因此最大浓度水平相对于没有辐射的情况增加，但羽流的厚度仅略有增加。
The explosion at the Buncefield oil depot in Hertfordshire, UK on 11 December 2005 produced the largest fire in Europe since the Second World War. The magnitude of the fire and the scale of the resulting plume thus present a stringent test of any mathematical model of buoyant plumes. A large-eddy simulation of the Boussinesq equations with suitable initial conditions is shown to reproduce the characteristics of the observed plume; both the height of the plume above the source and the direction of the downwind spread agree with the observations. This supports the use of the Boussinesq assumption, even for such a powerful plume as the one generated by the Buncefield fire. The presence of a realistic water vapour profile does not lead to significant additional latent heating of the plume, but does lead to a small increase in the final rise height of the plume due to the increased buoyancy provided by the water vapour. Our simulations include the interaction of radiation with the aerosol in the plume, and reproduce the observed optical thickness of the plume and the reduction of solar radiation reaching the ground. Far downwind of the source, solar radiation is shown to play a role in lofting the laterally spreading plume, but the manner in which it does so depends on the aerosol concentration. In the case of high aerosol concentration, the thickness of the plume increases; the incoming solar radiation is absorbed over such a small depth that only the top of the plume is lofted upwards and the level of maximum concentration remains almost unchanged relative to the case with no radiation. When the aerosol concentration is low, the whole plume is heated by the incoming solar radiation and the lofting is more coherent, with the result that the level of maximum concentration increases relative to the case with no radiation, but the thickness of the plume increases only slightly.