Propagation of smoldering combustion and its blow-off phenomena are of practical importance in evaluating the fire dynamics of solid fuels, but the scientific understanding is still limited. In this work, we quantify the smoldering propagation rates on consolidated biomass and the blow-off limits under concurrent and opposed external airflows up to 50 m/s. The incense cylinders with different diameters (1.5–5.0 mm) and densities (720–1,100 kg/m³) are tested. As the airflow velocity increases, the smoldering propagation rate first increases to its maximum value (Oxygen-limited Regime) and subsequently remains stable (Thermal Regime), regardless of the airflow direction. Afterward, it slightly decreases (Chemical Regime) until blow-off, and the blow-off of opposed smoldering is easier, similar to the pattern of flame spread. The blow-off airflow velocity (13–46 m/s) of smoldering combustion is around ten times larger than that of flaming combustion, and it decreases as the fuel diameter or density increases. This work advances the fundamental understanding of the smoldering propagation, blow-off, and its persistence; thus, helping guide the fire suppression strategies of smoldering.

阴燃燃烧的传播及其吹散现象在评估固体燃料的火灾动力学方面具有重要的实际意义，但科学认识仍然有限。在这项工作中，我们量化了固结生物质的阴燃传播速率和高达 50 m/s 的并发和反向外部气流下的吹气限制。不同直径（1.5-5.0 mm）和密度（720-1,100 kg/m ³) 进行测试。随着气流速度的增加，阴燃传播速率首先增加到其最大值（氧气限制状态），然后保持稳定（热状态），无论气流方向如何。之后，它稍微降低（Chemical Regime）直到吹掉，并且相反阴燃的吹掉更容易，类似于火焰蔓延的模式。阴燃燃烧的吹出气流速度（13-46 m/s）比有焰燃烧大十倍左右，并且随着燃料直径或密度的增加而减小。这项工作促进了对阴燃传播、吹散及其持续性的基本理解；因此，有助于指导阴燃的灭火策略。