Structure and dynamics of highly turbulent premixed combustion
Structure and dynamics of highly turbulent premixed combustion
复制标题
DOI：
10.1016/j.pecs.2020.100900
复制
发表时间：
2021-07
影响因子：
29.5
通讯作者：
A. Steinberg;P. Hamlington;Xinyu Zhao
中科院分区：
文献类型：
--
作者：
A. Steinberg;P. Hamlington;Xinyu Zhao
湍流预混燃烧涉及跨越广泛的空间和时间尺度的同时和相互作用的流体、化学和传输现象。许多实际的燃烧装置--例如燃气涡轮机燃烧室、加力燃烧室和冲压发动机--以湍流运行，所述湍流包含的长度和时间尺度小于与预混火焰传播相关的长度和时间尺度。本文回顾了目前的知识和理解预混火焰在这种“高度湍流”的条件下，包括湍流的火焰和湍流的火焰的影响。在这些条件下，湍流的流体运动可以有领先的顺序的火焰热化学结构，标量梯度，和由此产生的标量动力学的影响。与此同时，湍流本身受到火焰放热的影响，导致与经典的非反应湍流和较低强度的火焰中的湍流相比存在差异。因此，我们的目标是解决以下首要问题：（a）什么是高度湍流预混火焰，我们如何描述它们，以及它们的一些宏观行为是什么？(b)火焰的热化学状态、标量梯度、扩散和火焰结构的其他方面是如何受到强烈湍流的影响的？(c)在通量、光谱、动能和其他相关量方面，火焰的存在如何影响湍流的结构和动力学？我们还提供了一个关键的知识差距和未来的研究方向展望的总结。
Turbulent premixed combustion involves simultaneous and mutually interacting fluid, chemical, and transport phenomena spanning a wide range of spatial and temporal scales. Many practical combustion devices – such as gas turbine combustors, afterburners, and ramjets – operate with turbulent flows that contain length and time scales smaller than those associated with premixed flame propagation. This paper reviews current knowledge and understanding of premixed flames at such “highly turbulent” conditions, including the effects of turbulence on the flame and of the flame on turbulence. At these conditions, turbulent fluid motions can have a leading-order effect on the flame thermochemical structure, scalar gradients, and the resultant scalar dynamics. At the same time, the turbulent flow itself is affected by heat release from the flame, resulting in differences compared to classical non-reacting turbulence and to turbulence in flames at lower intensities. We therefore aim to address the following overarching questions: (a) What are highly turbulent premixed flames, how do we characterize them, and what are some of their macroscale behaviors? (b) How are the flame thermochemical states, scalar gradients, diffusion, and other aspects of the flame structure affected by intense turbulence? (c) How are the structure and dynamics of the turbulence affected by the presence of the flame in terms of fluxes, spectra, kinetic energy, and other relevant quantities? We also provide a summary of critical knowledge gaps and an outlook for future research directions.