空间时空表面温度测量解决火焰壁相互作用的弱H2空气和CH4空气火焰使用热量测量
Anthony O Ojo1, Abhijit Padhiary1, Brian Peterson1
1Institute of Multiscale Thermofluids, School of Engineering, The University of Edinburgh, Edinburgh, UK.
概括
温度计测量了来自气和甲气火焰的墙壁温度分布. 气火焰表现出明显的条纹,而甲火焰表现出纹,与易斯数的差异有关,并影响了热传递.
科学领域:
- 燃烧科学是一种科学.
- 热传递是一种热传递.
- 流体动力学 流体动力学
背景情况:
- 了解火焰壁相互作用对于过渡热传递分析至关重要,特别是对于具有独特燃烧不稳定的火焰.
- 量化墙壁温度分布为热流动动力学提供了洞察力.
研究的目的:
- 测量和比较来自稀疏气和甲气火焰的时空壁温度分布.
- 为了将火焰动力学与墙壁热 signature 相关联,并调查易斯数的影响.
- 检查通道间距对墙壁热损失的影响,研究火焰中的不稳定性.
主要方法:
- 使用ScVO4:Bi3+的温度计绘制墙壁温度 (Twall),分辨率为180μm/像素,重复频率为1kHz.
- 结合化学发光成像与度温度计,以将火焰特征与热特征相关联.
- 在一个带有不同通道间隔的双墙通道室中进行了实验.
主要成果:
- 的H2-空气火焰 (Φ=0.56) 由于指形结构,显示了交替的高/低温垂直条纹.
- CH4-空气火焰 (Φ=1) 显示出更大规模的纹,有明显的峰 (上方的Twall) 和尖端 (下方的Twall).
- 归因于易斯数的差异 (H2-空气:0.39,CH4-空气:0.94);H2-空气中的热扩散不稳定性造成了显著的热流.
结论:
- 火焰形态和易斯数显著影响时空壁温度分布.
- 即使是不稳定的瘦火焰也可以强加大量的热流,与具有更高功率的火焰相比.
- 通道间距影响墙壁的热量损失,较大的比率会增加热量损失.
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