Cui Wuquan, Dowling Joseph L, Hajilou Mohammadhadi, Huffman Mitchell, Pawar Bhushan, Aurell Johanna, Wang Qingsheng, Oran Elaine, Stone Karen N, Gollner Michael J
Department of Mechanical Engineering, University of California, Berkeley, California 94702-5800, United States.
Shiley School of Engineering, University of Portland, Portland, Oregon 97203, United States.
Fuel (Lond). 2026 Jan 1;403. doi: 10.1016/j.fuel.2025.136093.
Fire whirls, a combustion-intensifying phenomenon, offer potential for cleaner, more efficient burns with reduced emissions in environmental applications like oil spill remediation. While most knowledge of fire whirls stems from laboratory-scale experiments, and only a limited subset of these experiments has captured emissions, this study addresses a critical research gap by conducting one of the largest controlled fire whirl experiments to date, focusing on enhancing in-situ burning. Using a 1.5-meter diameter crude oil pool with 15 mm and 40 mm slick thicknesses on an open water surface, fire whirls were successfully generated within a 5-meter-tall three-wall structure under the influence of various wind conditions. Measurements of flame geometry, flow velocity, temperature profiles, heat flux, mass consumption, and emissions were compared to pool fires. Results revealed that fire whirls, with mean flame heights nearly double those of pool fires, increased burning rates by 40% and reduced soot emissions by 40%. The highest fuel consumption efficiency of 95% was achieved in a 15 mm slick thickness fire whirl experiment, while in other fire whirl experiments, especially those with 40 mm slick thickness, premature extinguishment was observed lowering ultimate fuel consumption efficiencies. Enhanced performance compared to traditional pool fires suggests that fire whirls might be more effective for in-situ burning, however this efficiency is currently only achieved under calm ambient conditions. This study discusses the potential interactive effects of ambient conditions, configuration sizing, and boilover phenomenon on fire whirl dynamics, highlighting the need of continued research across scales to optimize configurations and mitigate detrimental emissions, thereby enhancing the efficacy of in-situ burning in large-scale oil spill scenarios.
火旋风是一种强化燃烧的现象，在诸如溢油清理等环境应用中，它为更清洁、更高效的燃烧以及减少排放提供了潜力。虽然关于火旋风的大多数知识都源于实验室规模的实验，而且这些实验中只有有限的一部分测量了排放情况，但本研究通过进行迄今为止最大规模的受控火旋风实验之一，填补了一项关键的研究空白，重点是加强原位燃烧。在开放水面上使用一个直径1.5米的原油池，油膜厚度分别为15毫米和40毫米，在各种风况的影响下，在一个5米高的三壁结构内成功产生了火旋风。将火焰几何形状、流速、温度剖面、热通量、质量消耗和排放的测量结果与池火进行了比较。结果表明，火旋风的平均火焰高度几乎是池火的两倍，燃烧速率提高了40%，烟尘排放减少了40%。在一次15毫米油膜厚度的火旋风实验中实现了最高95%的燃料消耗效率，而在其他火旋风实验中，特别是那些油膜厚度为40毫米的实验中，观察到过早熄灭，降低了最终燃料消耗效率。与传统池火相比性能的提高表明，火旋风可能对原位燃烧更有效，然而目前这种效率仅在平静的环境条件下才能实现。本研究讨论了环境条件、结构尺寸和沸溢现象对火旋风动力学的潜在相互作用影响，强调需要跨尺度持续研究以优化结构并减少有害排放，从而提高大规模溢油场景中原位燃烧的效果。
