墙壁温度对尺度和流统计数据的影响 在流边界层内的预混合火焰墙相互作用期间
Sanjeev Kr Ghai1,2, Umair Ahmed1, Nilanjan Chakraborty1
1School of Engineering, Newcastle University, Newcastle-Upon-Tyne, NE1 7RU UK.
概括
在乱的V-火焰相互作用中研究热壁边界条件揭示了墙壁温度升高会减少火焰灭距离. 这些条件显著影响流特性,这对于准确的模拟至关重要.
科学领域:
- 燃烧科学是一种科学.
- 动荡的流动是动荡的流动
- 计算流体动力学的流体动力学.
背景情况:
- 在燃烧装置中,火焰壁相互作用至关重要.
- 流的V-火焰具有复杂的流动力学.
- 热边界条件影响着火焰的行为和热传递.
研究的目的:
- 为了研究同热和热壁边界条件对预混合V火焰的影响.
- 分析墙壁温度对火焰火和热流的影响.
- 了解热条件对流度指标和标尺消散的影响.
主要方法:
- 流道流动的直接数值模拟 (DNS) 使用预混合V火焰.
- 实施异热 (恒定未燃或升温) 和附热壁条件.
- 分析火焰的行为,传热,摩擦速度,标尺消散和流量.
主要成果:
- 增加的墙壁温度降低了最小的火焰灭距离,并增加了墙壁的热量流.
- 在边界条件中观察到的进度变量和温度行为的明显变化.
- 摩擦速度,雷诺兹应力,动动能和散射速率都受到热边界条件的显著影响.
结论:
- 热壁边界条件在火焰壁相互作用动态中起着至关重要的作用.
- 这些发现凸显了模拟中对流关闭的热效应精确建模的重要性.
- 墙壁温度升高会导致更强烈的流和传热现象.
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