REG: Injection-Seeded Nd:YAG Laser for PLIF and CARS Diagnostic Techniques

建议编号：CTS96-10402首席研究员：达顿这是一笔赠款，用于购买一台用于支持两个正在进行的流体动力学研究项目的注入种子激光器。第一个项目旨在获得高雷诺数喷流和剪切层中分子混合的定量、时间分辨测量结果。为此开发的诊断技术使用从一个流中播种的冷化学示踪剂和另一个流中播种的被动标量示踪剂同时激发平面激光诱导荧光(PLIF)，从而可以确定在分子水平上混合的射流流体的比例。第二个项目的目标是开发和应用一种新的三激光相干反斯托克斯-雷曼散射(CARS)技术，用于同时测量高速气流中的压力、温度和密度。在这些测量中，选择了第二泵浦激光和斯托克斯激光的波长，以便同时获得氮的振动光谱和纯转动光谱。压力和温度可以由三个激光CARS谱的形状确定，密度由状态方程得到。

ABSTRACT Proposal Number: CTS 96-10402 Principal Investigator: Dutton This is a grant to purchase an injection-seeded ND:YAG laser that will be dedicated to supporting two ongoing fluid dynamics research programs. The first project is aimed at obtaining quantitative, time-resolved measurements of molecular mixing in high Reynolds number jets and shear layers. The diagnostic technique that has been developed for this purpose uses the simultaneous excitation of planar laser-induced fluorescence (PLIF) from a cold chemistry tracer seeded in one stream and a passive scalar tracer seeded in another stream, such that the fraction of jet fluid mixed at the molecular level can be determined. The second project has as its objective the development and application of a new three-laser coherent anti-Stokes Raiman scattering (CARS) technique for the simultaneous measurement of pressure, temperature, and density in high-speed gas flows. For these measurements the wavelelgths of the second pump laser and the Stokes laser are selected so that the vibrational and pure rotational spectra of nitrogen are simultaneously acquired. Pressure and temperature can be determined from the shape of the three-laser CARS spectra, and density is obtained from an equation of state.