A fact often overlooked is that large-scale wildfires, although occurring infrequently, are responsible for the overwhelming majority of fire-related suppression costs, economic losses, and natural resources damages. Fortunately, the increasingly severe problems of large-scale wildfires worldwide have been receiving ever-growing academic attention. The high-intensity burning behaviors in wildfires stem from the significant interaction of combustion with heat transfer and atmospheric flow under complicated fuel, meteorology, and topography conditions. Therefore, mitigating measures against large-scale wildfire disasters have grown into a challenging research focus for combustion scientists. Research over the past century has resulted in incrementally enhanced insights into the mechanisms of combustion dynamics underlying the various erratic behaviors in large-scale wildfires, with theories and models of fire accelerations developed and validated. These advances are expected to improve the efficacy of large-scale wildfire predictions significantly. Nevertheless, the physical interpretation of the acceleration of large-scale wildfires is far from adequate and complete. This paper intends not to make a comprehensive review of the entire wildfire research field, but to depict an overall pattern of the essential factors that lead an initial small-scale spreading flame to a large-scale wildfire beyond control. It is outlined that the complicated transformation of fuel preheating mechanisms determines the growth of surface fire spread, while varied large-size flame fronts and unique spread modes induced in specific fire environments play an essential role in fire spread acceleration. Additionally, multiple fires burning and merging often act as crucial steps for accelerating surface fire spread, generating large-size flames, and triggering unique spread modes. These major potential factors strike the energy balance of a low-intensity wildfire and push it to a high-intensity state. Several issues regarding intensely burning behaviors in large-scale wildfires are selected for in-depth discussions, for which an overview of the progress and challenges in research is presented. It is concluded that the fundamental exploration targeted at developing application tools capable of dealing with large-scale wildfires remains at its early stages. Opportunities for innovation are abundant, yet systematic and long-term research programs are required.

一个经常被忽视的事实是，大规模的野火虽然很少发生，但却是造成绝大多数与火有关的灭火成本，经济损失和自然资源破坏的原因。幸运的是，全球范围内日益严重的野火问题已引起越来越多的学术关注。野火中的高强度燃烧行为源于在复杂的燃料，气象和地形条件下燃烧与热传递和大气流动之间的显着相互作用。因此，针对大规模野火灾难的缓解措施已成为燃烧科学家一项具有挑战性的研究重点。过去一个世纪的研究导致对大规模野火中各种不稳定行为所依据的燃烧动力学机制的认识得到了逐步增强，并开发并验证了火灾加速的理论和模型。这些进展有望显着提高大规模野火预测的效力。然而，对大规模野火加速的物理解释还远远不够而完整。本文的目的不是对整个野火研究领域进行全面回顾，而是要描述导致最初的小规模蔓延火焰导致无法控制的大规模野火的基本因素的整体模式。概述了燃料预热机理的复杂转变决定了地面火势蔓延的增长，而在特定的火灾环境中引起的各种大尺寸火焰前锋和独特的扩散模式在加速火焰扩散中起着至关重要的作用。此外，多次燃烧和融合通常是加速表面火势蔓延，产生大尺寸火焰并触发独特蔓延模式的关键步骤。这些主要的潜在因素破坏了低强度野火的能量平衡，并将其推向高强度状态。选择了与大规模野火中强烈燃烧行为有关的几个问题进行深入讨论，并在此概述了研究的进展和挑战。结论是，针对开发能够处理大规模野火的应用程序工具的基础探索仍处于早期阶段。创新的机会很多，