Capturing multi-regime combustion in turbulent flames with a virtual chemistry approach
Capturing multi-regime combustion in turbulent flames with a virtual chemistry approach
复制标题
使用虚拟化学方法捕获湍流火焰中的多态燃烧
DOI：
10.1016/j.proci.2020.06.131
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发表时间：
2020
影响因子：
4.4
通讯作者：
B. Fiorina
中科院分区：
文献类型：
--
作者：
G. Maio;M. Cailler;N. Darabiha;B. Fiorina
在工业燃烧室中会遇到多种火焰状态，其中预混火焰区域、分层火焰区域和非预混火焰区域可以共存。为了获得污染物形成预测的预测工具，化学火焰建模必须考虑到这种复杂的火焰结构的影响。本文的目的是应用和比较两个简化的化学模型层流和湍流多制度火焰配置，以分析其预测火焰结构和CO形成的能力。挑战的方法是（i）预混火焰为基础的列表化学方法，其热化学变量的参数化的混合物分数和一个进步变量，和（ii）虚拟的化学方案已被优化，以检索规范的预混和非预混1-D层流火焰的属性。首先应用该方法计算了一系列层流部分预混甲烷-空气逆流火焰。结果进行了比较，详细的化学模拟。这两种方法都再现了热火焰结构，但只有虚拟化学捕获的CO形成在所有范围内的当量比从化学计量预混火焰纯非预混火焰。最后，两个化学模型结合加厚火焰模型的LES的挑战与非均匀入口，悉尼非均匀燃烧器的试点湍流射流火焰。温度和CO质量分数径向分布的平均值和RMS进行比较，可用的实验数据。还研究了混合分数空间中的散射数据以及数值和实验数据的Wasserstein度量。分析再次证实，虚拟化学的方法是能够占多制度的湍流燃烧的CO生成的影响。
Multiple flame regimes are encountered in industrial combustion chambers, where premixed, stratified and non-premixed flame regions may coexist. To obtain a predictive tool for pollutant formation predictions, chemical flame modeling must take into account the influence of such complex flame structure. The objective of this article is to apply and compare two reduced chemistry models on both laminar and turbulent multi-regime flame configurations in order to analyze their capabilities in predicting flame structure and CO formation. The challenged approaches are (i) a premixed flamelet-based tabulated chemistry method, whose thermochemical variables are parameterized by a mixture fraction and a progress variable, and (ii) a virtual chemical scheme which has been optimized to retrieve the properties of canonical premixed and non-premixed 1-D laminar flames. The methods are first applied to compute a series of laminar partially-premixed methane-air counterflow flames. Results are compared to detailed chemistry simulations. Both approaches reproduced the thermal flame structure but only the virtual chemistry captures the CO formation in all ranges of equivalence ratio from stoichiometry premixed flame to pure non-premixed flame. Finally, the two chemical models combined with the Thickened Flame model for LES are challenged on a piloted turbulent jet flame with inhomogeneous inlet, the Sydney inhomogeneous burner. Mean and RMS of temperature and CO mass fraction radial profiles are compared to available experimental data. Scatter data in mixture fraction space and Wasserstein metric of numerical and experimental data are also studied. The analyses confirm again that the virtual chemistry approach is able to account for the impact of multi-regime turbulent combustion on the CO formation.