The evolution of smoldering fires in biomass stored in lab-scale silos with additional fuel material supplied repeatedly, has been studied. The direct effects of the added material on the sample are: cooling, enhanced thermal insulation, and facilitation of more intense combustion at a later stage. This article focuses on the cooling, which leads to an almost instantaneous reduction in the combustion rate. Surprisingly, this reduction does not vary only with the amount of material refilled – but also depends strongly on the stage of the smoldering process. This demonstrates that the underlying smoldering processes merely to a certain degree are regularized by the periodic refillings. Quantitatively, the functional relationship between the refilled amount and the change in combustion rate caused by the refilling was determined. The results displays four regimes, that reflect different stages of the smoldering process at the time of the refilling. Using the Arrhenius equation, we find for one of these regimes an expression for the ratio of combustion rates (immediately after to immediately before the refill) as function of the amount of added material. This expression contains only one free (undetermined) parameter. We determine the value of this parameter from the data and demonstrate that this value is consistent with a simple model for how the sudden cooling occurs spatially in the sample.

已经研究了储存在实验室规模筒仓中并重复供应额外燃料材料的生物质中阴燃火灾的演变。添加材料对样品的直接影响是：冷却、增强绝热性和促进后期更强烈的燃烧。本文重点介绍冷却，这会导致燃烧率几乎瞬间降低。令人惊讶的是，这种减少不仅与重新填充的材料量有关，而且在很大程度上取决于阴燃过程的阶段。这表明，潜在的阴燃过程仅在一定程度上通过定期再填充来规范化。定量地确定了再填充量与再填充引起的燃烧率变化之间的函数关系。结果显示了四种状态，它们反映了再填充时阴燃过程的不同阶段。使用 Arrhenius 方程，我们发现对于这些状态之一，燃烧速率（紧接在再填充之后到紧接在再填充之前）的比率作为添加材料的量的函数的表达式。此表达式仅包含一个空闲（未确定）参数。我们根据数据确定该参数的值，并证明该值与样品中突然冷却如何在空间上发生的简单模型一致。我们发现对于这些状态之一，燃烧率（紧接在再填充之后到紧接在再填充之前）的比率的表达式作为添加材料的量的函数。此表达式仅包含一个空闲（未确定）参数。我们根据数据确定该参数的值，并证明该值与样品中突然冷却如何在空间上发生的简单模型一致。我们发现对于这些状态之一，燃烧率（紧接在再填充之后到紧接在再填充之前）的比率的表达式作为添加材料的量的函数。此表达式仅包含一个空闲（未确定）参数。我们根据数据确定该参数的值，并证明该值与样品中突然冷却如何在空间上发生的简单模型一致。