Turbulent Premixed LES Combustion Models Based on Fractal Flame Surface Density Concepts
Turbulent Premixed LES Combustion Models Based on Fractal Flame Surface Density Concepts
复制标题
基于分形火焰表面密度概念的湍流预混 LES 燃烧模型
DOI：
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发表时间：
2014
期刊：
影响因子：
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通讯作者：
M. Pfitzner
中科院分区：
文献类型：
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作者：
U. Allauddin;R. Keppeler;M. Pfitzner
随着计算能力的提高，大涡模拟（LES）被广泛用于研究和更好地理解湍流燃烧。人们提出了多种亚网格燃烧模型来研究LES中的预混燃烧。其中一个可以利用的物理方面是已在几个实验工作中得到证实的预混火焰的分形特性。本文研究了已建立的基于火焰表面分形特征的亚网格火焰表面密度燃烧模型的简化版本的性能。在理论模型、实验和直接数值模拟数据库的基础上推导了原始模型，并用现有文献的数据验证了其性能。讨论了对所建立的火焰表面密度模型的简化，并与原模型进行了对比，验证了其性能。其次，对两种模型在典型火花点火发动机和工业燃气轮机工况下的数值模拟结果进行了对比实验验证。结果表明，原始模型和简化模型均适用于常压和高压条件下低至高湍流预混燃烧的LES。ASME版权所有©2014
With increasing computational power, Large Eddy Simulation (LES) is being widely used to study and develop a better understanding of turbulent combustion. A variety of subgrid combustion models have been proposed to investigate premixed combustion in LES. One of the physical aspects that can be exploited, are the fractal characteristics of premixed flames which have been confirmed in several experimental works. In this work the performance of a simplified version of an already established sub-grid flame surface density combustion model, which is based on the fractal characteristics of the flame surface is investigated. The original model was derived on the basis of theoretical models, experimental and direct numerical simulations databases and its performance was validated with data from the available literature. The simplifications to the established flame surface density model are discussed, and its performance is validated in comparison to the original model. Secondly numerical simulations with both models at conditions typical for spark-ignition engines and industrial gas turbines are validated against experimental data. It is found that both original and simplified models are suitable for LES of low to high turbulent premixed combustion in ambient and elevated pressure conditions.Copyright © 2014 by ASME