Turbulent Momentum Flux Behavior above a Fire Front in an Open-Canopied Forest
Turbulent Momentum Flux Behavior above a Fire Front in an Open-Canopied Forest
复制标题
开放林冠森林中火锋上方的湍流动量通量行为
DOI：
10.3390/atmos12080956
复制
发表时间：
2021
期刊：
影响因子：
2.9
通讯作者：
M. Patterson
中科院分区：
文献类型：
--
作者：
W. Heilman;K. Clark;X. Bian;J. Charney;S. Zhong;N. Skowronski;Michael R. Gallagher;M. Patterson
野火锋面附近的大气湍流环流在动量进出燃烧区的转移中起着重要作用，这反过来又可能影响野火的行为和蔓延。动量的垂直湍流传递通过单独的扫掠、喷射、向外相互作用和向内相互作用事件来完成，统称为扫掠-喷射动力学。本研究探讨了发生前，期间和之后的表面火锋在规定的火灾实验中进行的开放式林冠在新泽西松树荒地森林通过清扫喷射动力学。高频（10 Hz），基于塔，声波风速计测量的水平和垂直风速分量在火灾前附近的被用来评估发生的相对频率的不同类型的动量通量事件，其贡献的整体动量通量，和他们的周期性模式。观测结果表明，在开放式林冠的森林表面火锋的存在下，可以大大改变通常发生在火灾时，不存在的清扫喷射动力学。特别是，扫描事件导致高水平动量的空气从上面向下运输被发现是更突出的火灾前通道期间。
Atmospheric turbulent circulations in the vicinity of wildland fire fronts play an important role in the transfer of momentum into and out of combustion zones, which in turn can potentially affect the behavior and spread of wildland fires. The vertical turbulent transfer of momentum is accomplished via individual sweep, ejection, outward interaction, and inward interaction events, collectively known as sweep-ejection dynamics. This study examined the sweep-ejection dynamics that occurred before, during, and after the passage of a surface fire front during a prescribed fire experiment conducted in an open-canopied forest in the New Jersey Pine Barrens. High-frequency (10 Hz), tower-based, sonic anemometer measurements of horizontal and vertical wind velocity components in the vicinity of the fire front were used to assess the relative frequencies of occurrence of the different types of momentum-flux events, their contributions to the overall momentum fluxes, and their periodicity patterns. The observational results suggest that the presence of surface fire fronts in open-canopied forests can substantially change the sweep-ejection dynamics that typically occur when fires are not present. In particular, sweep events resulting in the downward transport of high horizontal momentum air from above were found to be more prominent during fire-front-passage periods.
影响因子：
3.1
作者：
Clements, Craig B.;Kochanski, Adam K.;Teske, Casey
通讯作者：
Teske, Casey