用于高速PLIF诊断的可调谐激光技术研究
发布时间：2018-10-20 09:53
【摘要】：平面激光诱导荧光(Planar Laser Induced Fluorescence,PLIF)技术是使用平面激光脉冲激励荧光来记录瞬态流场和火焰结构的技术,利用激光对自由基团和离子的激发,通过对荧光的强度和二维空间的分布的分析,可以得到某些气体分子的温度分布,浓度分布以及火焰结构等信息。PLIF技术具有高空间分辨率,响应时间短,高灵敏度的特点,是目前主要的检测快速变化的流场的技术。PLIF技术通常需要使用高重频大能量可调谐的染料激光器来反映快速变化的流场,针对高速PLIF诊断对高重频大能量窄线宽的可调谐激光技术的需求,本文开展高重频大能量可调谐染料激光器的研究。对于高重频大能量可调谐激光器的时域特性,基于染料流动热管理和液体流动稳定性得到了了高重频下的染料循环系统的流速为10m/s,测量了激光器的输出能量波动约为4%,最后,测量了可调谐激光器的输出脉宽,可稳定在8ns。对于高重频大能量可调谐激光器的频域特性,研究了可调谐激光的线宽压窄技术,实现使用光栅进行线宽压窄,研究了可调谐激光的波长调谐技术,研究了可调谐激光的倍频条件,针对以上技术进行了实际测量,以及理论分析。对于高重频大能量可调谐激光器的强度特性,测量了染料激光器的转换效率,基频光的转换效率约为20%,基频光的输出可达6m J,研究了振荡级扩束镜对激光输出的影响以及泵浦光偏振特性对激光输出的影响,最后,开展倍频效率的理论分析,其实际测量结果可达33%,倍频光的输出可达2.2m J。
[Abstract]:The planar laser-induced fluorescence (Planar Laser Induced Fluorescence,PLIF) technique is a technique of recording the transient flow field and flame structure by using planar laser pulse excitation fluorescence, and using laser to excite free radical groups and ions. Through the analysis of fluorescence intensity and two-dimensional spatial distribution, the temperature distribution, concentration distribution and flame structure of some gas molecules can be obtained. PLIF technology has the characteristics of high spatial resolution, short response time and high sensitivity. PLIF technology usually requires a dye laser with high repetition frequency and tunable energy to reflect the rapidly changing flow field. In view of the demand of high speed PLIF diagnosis for tunable laser technology with high repetition frequency, large energy and narrow linewidth, the research of high repetition frequency and large energy tunable dye laser is carried out in this paper. For the time domain characteristics of high repetition frequency and high energy tunable laser, based on the thermal management of dye flow and the stability of liquid flow, the flow rate of the dye cycle system at high repetition frequency is 10 m / s, and the output energy fluctuation of the laser is about 4. Finally, The output pulse width of the tunable laser is measured, which can be stabilized at 8ns. For the frequency domain characteristic of high repetition frequency and large energy tunable laser, the linewidth and pressure narrowing technology of tunable laser is studied, and the wavelength tunable technology of tunable laser is studied by using grating to narrow line width. The frequency doubling condition of tunable laser is studied, and the practical measurement and theoretical analysis are carried out. For the intensity characteristics of high repetition frequency and high energy tunable laser, the conversion efficiency of dye laser is measured. The conversion efficiency of the fundamental frequency light is about 20 and the output of the fundamental frequency light can reach 6mJ. The influence of the oscillatory beam expander on the laser output and the effect of the polarization characteristics of the pump light on the laser output are studied. Finally, the theoretical analysis of the frequency doubling efficiency is carried out. The practical measurement results can reach 33 and the output of frequency doubling light can reach 2.2 m J.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN248
本文编号：2282791
[Abstract]:The planar laser-induced fluorescence (Planar Laser Induced Fluorescence,PLIF) technique is a technique of recording the transient flow field and flame structure by using planar laser pulse excitation fluorescence, and using laser to excite free radical groups and ions. Through the analysis of fluorescence intensity and two-dimensional spatial distribution, the temperature distribution, concentration distribution and flame structure of some gas molecules can be obtained. PLIF technology has the characteristics of high spatial resolution, short response time and high sensitivity. PLIF technology usually requires a dye laser with high repetition frequency and tunable energy to reflect the rapidly changing flow field. In view of the demand of high speed PLIF diagnosis for tunable laser technology with high repetition frequency, large energy and narrow linewidth, the research of high repetition frequency and large energy tunable dye laser is carried out in this paper. For the time domain characteristics of high repetition frequency and high energy tunable laser, based on the thermal management of dye flow and the stability of liquid flow, the flow rate of the dye cycle system at high repetition frequency is 10 m / s, and the output energy fluctuation of the laser is about 4. Finally, The output pulse width of the tunable laser is measured, which can be stabilized at 8ns. For the frequency domain characteristic of high repetition frequency and large energy tunable laser, the linewidth and pressure narrowing technology of tunable laser is studied, and the wavelength tunable technology of tunable laser is studied by using grating to narrow line width. The frequency doubling condition of tunable laser is studied, and the practical measurement and theoretical analysis are carried out. For the intensity characteristics of high repetition frequency and high energy tunable laser, the conversion efficiency of dye laser is measured. The conversion efficiency of the fundamental frequency light is about 20 and the output of the fundamental frequency light can reach 6mJ. The influence of the oscillatory beam expander on the laser output and the effect of the polarization characteristics of the pump light on the laser output are studied. Finally, the theoretical analysis of the frequency doubling efficiency is carried out. The practical measurement results can reach 33 and the output of frequency doubling light can reach 2.2 m J.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN248
【参考文献】
相关期刊论文 前6条
1 王墨戈;陆启生;许晓军;郭少锋;;宽谱染料激光器的数值模型及实验验证[J];物理学报;2008年03期
2 吴逢铁,张文珍;BBO晶体相位匹配允许角对倍频效率的影响[J];华侨大学学报(自然科学版);1997年04期
3 严家祥,余斌;三维不可压缩层流、转捩、湍流边界层的数值计算[J];空气动力学学报;1991年02期
4 周建英;黄作柱;余振新;罗黎明;;光栅掠入射脉冲染料激光器工作特性的研究[J];激光技术;1990年03期
5 学身;;国外染料激光器发展现状[J];激光与红外;1980年06期
6 颜炳玉;;脉冲式可调谐染料激光器的性能研究[J];激光;1980年03期
相关博士学位论文 前5条
1 刘芳;窄线宽染料激光稳频系统设计、实现及应用[D];中国科学院研究生院（武汉物理与数学研究所）;2013年
2 姜玉刚;高性能固体染料激光介质研制及可调谐激光输出特性研究[D];哈尔滨工业大学;2011年
3 王墨戈;液体激光器流动热管理的研究及应用[D];国防科学技术大学;2009年
4 万勇;纳秒光学参量振荡器及其应用技术研究[D];电子科技大学;2006年
5 李麦亮;激光光谱诊断技术及其在发动机燃烧研究中的应用[D];国防科学技术大学;2004年
相关硕士学位论文 前1条
1 贾博阳;本生灯火焰羟基的平面激光诱导荧光测量方法研究[D];哈尔滨工业大学;2013年
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