Investigation and Application of Fundamental Phenomena of Turbulent Premixed Combustion in a High-Pressure Environment

高压环境下湍流预混燃烧基本现象的研究与应用

• 批准号: 10450079
• 负责人: KOBAYASHI Hideaki
• 金额: $ 4.99万
• 依托单位: TOHOKU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10450079/
• 关键词: High-Pressure Combustion; Turbulent Combustion; LIF; Turbulent Burning Velocity; Instability; Fractal; Cut-off Scale; 予混合燃焼; OHラジカル; 吸収スペクトル

Turbulent premixed flames stabilized in a high-pressure atmosphere was studied with the aim of basic elucidation of phenomena of the high-pressure turbulent combustion which has not been explored precisely. The relationship between turbulence characteristics and turbulent flame structure under high pressure was clarified. Investigation of pressure effect for the fractal properties and turbulent burning velocity under high pressure were also made.The laminar flow nozzle-burner is installed in the pressure chamber, and OH-LIF technique were investigated at pressures from the atmospheric pressure up to 3.0 MPa. (0, 0) band and (1, 0) band of the OH radical were excited by an OPO tunable laser and a dye laser pumped by a Nd-YAG laser. The relationship between OH-LIF intensity and pressure was examined. In addition, a simulation considering effects of the broadening of laser line width and absorption spectrum was made and also compared with the experimental result. As the result, it was cla … More rified that the effects of the absorption spectrum broadening was large for the LIF intensity degradation with the increase in pressure. Although the LIF intensity for larger laser line width is smaller than the case of smaller laser line width at atmospheric pressure, the decrease in LIF intensity with pressure is small for larger laser line width. It was proven that to estimate LIF intensity degradation under the high pressure was possible by calculating the overlap integral of laser spectrum profiles and absorption line spectral profiles. From these findings, guideline for the measurement condition of OH-PLIF at high-pressure was established.In continuing, the OH-PLIF method was applied to the instantaneous tomographic imaging of high-pressure turbulent flames. Especially, the fractal analysis of the OH-PLIF image was carried out as the technique which can quantitatively evaluate refinement and complication of the turbulent flame structure. As the result, it was proved that the fractal dimension for high-pressure flame was larger than atmospheric pressure flame even for equal u'/SィイD2LィエD2. The fractal inner cutoff decreased with pressure, but it was proven that the fractal inner cutoff was almost fixed in almost whole range of u'/SィイD2LィエD2 at high pressure. When various characteristic scales such as turbulent scales were compared with the fractal inner cutoff, it was proved that a characteristic instability scale, which corresponds to disturbance scale of maximum growth rate for the hydrodynamic instability, was well correlated to the fractal inner cutoff. These new findings which the hydrodynamic instability has dominant effects at high pressure were also confirmed by the observation of the flame instability with no initial turbulence in flow at high pressure. Less

本文对稳定在高压大气中的湍流预混火焰进行了研究，目的是从根本上阐明高压湍流燃烧现象，而这种现象尚未得到精确的研究。阐明了高压下湍流特性与湍流火焰结构的关系。在压力室中安装层流燃烧器，在常压至3.0MPa的压力范围内对OH-LIF技术进行了研究。OH自由基的（0，0）带和（1，0）带分别由OPO可调谐激光器和Nd-YAG激光器泵浦的染料激光器激发。检查了OH-LIF强度与压力之间的关系。此外，还考虑了激光线宽和吸收谱的展宽效应，进行了模拟计算，并与实验结果进行了比较。结果，这是一流的。 ...更多信息 结果表明，随着气压的增加，激光诱导荧光强度的衰减对吸收谱展宽的影响很大。虽然在大气压下，较大激光线宽的LIF强度小于较小激光线宽的情况，但对于较大激光线宽，LIF强度随压力的降低较小。通过计算激光光谱轮廓和吸收线光谱轮廓的重叠积分，证明了高压下激光诱导荧光强度衰减的估计是可能的。在此基础上，建立了高压条件下OH-PLIF的测量条件，并将OH-PLIF方法应用于高压湍流火焰的瞬态层析成像。特别地，对OH-PLIF图像进行分形分析，作为可以定量评价湍流火焰结构的精细化和复杂化的技术。结果表明，即使在相同的u ′/S_（？）D_2 L_（？）D_2的情况下，高压火焰的分形维数也大于常压火焰。分形内截止值随压力的增大而减小，但在高压下，分形内截止值在几乎整个u ′/S_（？）将湍流尺度等各种特征尺度与分形内截止尺度进行比较，证明了一个特征不稳定尺度与分形内截止尺度有很好的相关性，它对应于水动力不稳定性最大增长率的扰动尺度。这些新的发现，流体动力学不稳定性具有主导作用，在高压下没有初始湍流的火焰不稳定性的观察也证实了在高压下。少

项目成果

Kobayashi, H. and Kawazoe, Y.: "Flame Instability Effects on Smallest Wrinkling Scale and Burning Velocity of High-Pressure Turbulent Premixed Flames"Twenty-Eighth Symposium (International) on Combustion, The Combustion Institute. (submitted). (2000)

Kobayashi, H. 和 Kawazoe, Y.：“火焰不稳定性对高压湍流预混火焰最小起皱规模和燃烧速度的影响”第二十八届燃烧研讨会（国际），燃烧研究所。

H.KOBAYASHI: "LIF Measurements of Turbulent Premixed Flames in a High Pressure Environment" 5th ASME/JSME Joint Thermal Engineering Conference. (1999)

H.KOBAYASHI：“高压环境中湍流预混火焰的 LIF 测量”第五届 ASME/JSME 联合热工会议。

Kobayashi H.,Oyachi T.and Maruta K.: "LIF Measurement of Turbulent Premixed Flames in a High-Pressure Environment"5th ASME/JSME Joint Thermal Engineering Conference. AJTE99-6480 (1999)

Kobayashi H.、Oyachi T. 和 Maruta K.：“高压环境中湍流预混火焰的 LIF 测量”第五届 ASME/JSME 联合热工会议。

Kobayashi, H., Oyachi, T., and Maruta, K.: "LIF measurements of Turbulent Premixed Flames in a High-Pressure Environment"Fifth ASME/JSME Joint Thermal Engineering Conference, San Diego, USA. AJTE99-6480 (1999)

Kobayashi, H.、Oyachi, T. 和 Maruta, K.：“高压环境中湍流预混火焰的 LIF 测量”第五届 ASME/JSME 联合热工程会议，美国圣地亚哥。

Kobayashi H.et al.: "LIF Measurement of Turbulent Premixed Flames in a High-Pressure Environment"5th ASME/JSME Joint Thermal Engineering Conference. (AJTE 99-6480). (1999)

Kobayashi H.et al.：“高压环境中湍流预混火焰的 LIF 测量”第五届 ASME/JSME 联合热工会议。