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

基本信息

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

项目摘要

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

在高压大气中稳定了turberent的火焰，尚未精确地探索高压燃烧的高压燃烧。 - 在压力室中高的ISS，OH-LIF技术在大气中的压力下进行了3.0 MPa的压力，OPO可调激光激发了OH激发的带。 - YAG激光和压力。随着压力的增加，光谱宽度很大。激光光谱曲线的重叠和吸收线曲线的重叠作为可以定量评估细化和卷曲火焰结构的汇编的技术进行的。在高压下几乎固定了整个'/s II D2的范围。火焰不稳定性证实了高含量的主导性，而在希格h处没有初始湍流，较少的