RWTH Aachen University, Institute for Combustion Technology, 52056 Aachen, Germany.
Université de Lille I, 59655 Villeneuve d'Ascq, France.
Phys Rev E. 2017 Jun;95(6-1):063113. doi: 10.1103/PhysRevE.95.063113. Epub 2017 Jun 22.
The present interdisciplinary study combines electromagnetics and combustion to unveil an original and basic experiment displaying a spontaneous flame instability that is mitigated as the non-premixed sooting flame experiences a magnetic perturbation. This magnetic instability mitigation is reproduced by direct numerical simulations to be further elucidated by a flow stability analysis. A key role in the stabilization process is attributed to the momentum and thermochemistry coupling that the magnetic force, acting mainly on paramagnetic oxygen, contributes to sustain. The spatial local stability analysis based on the numerical simulations shows that the magnetic field tends to reduce the growth rates of small flame perturbations.
本跨学科研究将电磁学和燃烧学相结合,揭示了一个原创的基础实验,展示了非预混含碳火焰在受到磁场干扰时会出现自发的火焰不稳定性,并且这种不稳定性会随着磁场的变化而减弱。通过直接数值模拟再现了这种磁不稳定性的缓解,并通过流场稳定性分析进一步阐明了这一现象。磁场主要作用于顺磁性氧,通过对动量和热化学耦合的影响,在稳定过程中起到了关键作用。基于数值模拟的空间局部稳定性分析表明,磁场会降低小火焰扰动的增长率。