Instrumentation Development of Compact Laser Diagnostic Systems for the Combustion Experiments under Microgravity

微重力燃烧实验紧凑型激光诊断系统的仪器开发

基本信息

批准号：
08555241
负责人：
KADOTA Toshikazu
金额：
$ 12.16万
依托单位：
Osaka Prefecture University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1997
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08555241/
关键词：
Microgravity Combustion Laser Measurement Laser induced fluorescence Laser light scattering Droplet temperature Soot レーザ散乱法

项目摘要

The instrumentation development has been made of compact laser-based diagnostic systems which is applicable for the experimental study of the combustion processes under microgravity.A small drop shaft was newly developed which enabled the combustion experiments under microgravity during the period of time 0.8 s. The structure of the spherical flame and the soot shell were observed by using shadowgraph. Planar laser light scattering was applied for the visualization of two dimensional soot concentration profile in the droplet flame. A droplet burning in quiescent gaseous environment was irradiated with the sheet of an incident cw Argon laser or a pulsed YAG laser and the image of the scattered light intensity was detected with the use of a CCD camera via a band pass filter.OH concentration profile in the droplet flame was measured by using planar laser induced fluorescence. A sheet of an incident dye laser pumped with the second harmonic of a pulsed YAG laser was utilized as a light source and the fluorescence intensity was transmitted through a band pass filter, being detected by using a CCD camera with a gated image intensifier which was installed at the right angle to the incident laser light. This resulted in the successful visualization of two dimensional profile of OH concentration in the droplet flame.Laser induced fluorescence was applied for the remote probing of the temperature of the droplet surrounded by an envelope flame. A fuel droplet doped with a small amount of naphthalene and TMPD was subjected to the irradiation of the incident nitrogen laser. Resultant fluorescence intensity was detected by using an optical multichannel analyzer and the droplet fluorescing blue was photographed by a CCD camera. The droplet temperature was determined by measuring the ratio of the fluorescence intensities at two different wavelengths.

仪器开发是由基于紧凑的激光诊断系统制成的，该系统适用于微重力下燃烧过程的实验研究。新开发了一个小滴轴，从而在0.8 s时期实现了微重力下的燃烧实验。通过使用阴影图观察球形火焰和烟灰壳的结构。将平面激光散射用于液滴火焰中二维烟灰浓度曲线的可视化。在静止气体环境中燃烧的液滴被入射的CW氩激光或脉冲YAG激光器辐射，并使用平面激光诱导的荧光测量液滴火焰中的OOH浓度来检测散射光强度的图像。用脉冲YAG激光器的第二个谐波泵送的事件染料激光器被用作光源，并通过带带通滤波器的CCD摄像头传输荧光强度，该荧光强度通过带封闭的图像增强器进行检测到，该摄像头安装在与事件激光灯的正确角度。这导致了液滴火焰中OH浓度的二维轮廓的成功可视化。激光诱导的荧光用于远程探测被包膜火焰包围的液滴温度。用少量的萘和TMPD掺杂的燃料液滴受到入射氮激光的照射。通过使用光学多通道分析仪检测到结果荧光强度，并通过CCD摄像头拍摄了液滴荧光蓝色。通过测量两个不同波长的荧光强度之比来确定液滴温度。