Abstract Recent visual, PIV, and fs-CARS measurements show the multiple fundamental changes that occur when a hydrogen stand-burner flame is actuated by a dielectric-barrier-discharge (DBD). These are far more significant than in corresponding actuation without combustion. The un-actuated flame is conical and flickers at ∼ 10 Hz. As the DBD voltage is increased, the oscillations decrease then cease, the flame flattens and light emission significantly increase. We develop a simulation model that reproduces and allows us to analyze the mechanisms that underlie these changes. The main mechanisms are body forces due to charge sheaths, with radicals produced by plasma excitation playing a secondary role for the present conditions. The basic model introduced for charge density is based on a Poisson–Boltzmann description, with charge assumed to be in equilibrium with the potential. However, in this limit a constant-property plasma produces only an irrotational force, which we show fails to reproduce the observed vortex-ring. To correct this, we introduce a non-constant property, linearized Poisson–Boltzmann model, which thus includes charge-induced vorticity via the misalignment of the gradient of the screening length and the electric field. This reproduces the observations. For weak actuation, the vortex ring remains within the stoichiometric surface. This flame widens some, but flickers at the same frequency with reduced amplitude. Above 8 kV, a sudden increase in plasma extent occurs due to electrical breakdown on the outer dielectric surface facilitated by the flame lying now close to the actuator surface. This supports a broader plasma and consequently a broader vortex ring. The vortex ring moves outside of the stoichiometric surface, leading to a reduction of the flame surface, which is now ventilated by the air entrained by the vortex. This brings the flickering conical flame into a state that resembles a counter-flow flat flame.

中文翻译：

---

介质阻挡放电等离子体辅助氢扩散火焰。第 2 部分：建模和与实验的比较

摘要 最近的视觉、PIV 和 fs-CARS 测量显示了当氢气立式燃烧器火焰由介电屏障放电 (DBD) 驱动时发生的多种基本变化。这些比不燃烧的相应致动要重要得多。未驱动的火焰呈圆锥形，以~10 Hz 的频率闪烁。随着 DBD 电压的增加，振荡减少然后停止，火焰变平并且光发射显着增加。我们开发了一个模拟模型，可以重现并允许我们分析这些变化背后的机制。主要机制是由电荷鞘引起的体力，等离子体激发产生的自由基在当前条件下起次要作用。电荷密度的基本模型基于泊松-玻尔兹曼描述，假设电荷与电位平衡。然而，在这个极限中，恒定特性的等离子体只产生无旋力，我们表明它无法重现观察到的涡环。为了纠正这个问题，我们引入了一个非常数性质的线性泊松-玻尔兹曼模型，该模型因此包括通过屏蔽长度和电场的梯度错位引起的电荷感应涡度。这再现了观察结果。对于弱驱动，涡环保持在化学计量表面内。这种火焰扩大了一些，但以相同的频率闪烁，但幅度减小。高于 8 kV，由于靠近执行器表面的火焰促进了外电介质表面上的电击穿，等离子体范围会突然增加。这支持更宽的等离子体，因此支持更宽的涡环。涡流环移动到化学计量表面之外，导致火焰表面减少，现在通过涡流夹带的空气进行通风。这使闪烁的锥形火焰进入类似于逆流扁平火焰的状态。