Thermoacoustic instabilities are large-amplitude self-sustained oscillations of the acoustic field that are observed in various combustion systems.^1,2 They arise as the result of thermoacoustic feedback, i.e. positive feedback between the heat source (typically a flame) and the acoustic field inside the combustor. What starts as a small perturbation in the acoustic field amplifies the rate of heat release, which in turn amplifies the acoustic field; this process is repeated periodically, and high amplitudes are soon reached. Whether the feedback is positive depends on the system parameters. It may also be negative, in which case an initial perturbation decays. Efforts have been made by several research groups to understand and control this phenomenon. One can get an overview in the review articles of Candel,³ Lieuwen⁴ and Huang and Yang,⁵ in the books by Lieuwen and Yang⁶ and Poinsot and Veynante,⁷ and in Culick.⁸

中文翻译：

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用格林函数方法分析热声模式的相互作用

热声不稳定性是在各种燃烧系统中观察到的声场的大幅度自持振荡。^1,2它们是热声反馈的结果，即热源（通常是火焰）与燃烧器内部声场之间的正反馈。首先是对声场的微小扰动会放大放热率，继而又会放大声场。定期重复此过程，并很快达到高振幅。反馈是否为正取决于系统参数。它也可能是负的，在这种情况下，初始扰动会衰减。几个研究小组已经做出努力来理解和控制这种现象。您可以在Candel的评论文章中获得概述，³ Lieuwen和Yang ⁶以及Poinsot和Veynante的书⁷和Culick中的Lieuwen ⁴和Huang and Yang，⁵。⁸