Hammack Stephen D, Carter Campbell D, Skiba Aaron W, Fugger Christopher A, Felver Josef J, Miller Joseph D, Gord James R, Lee Tonghun
Opt Lett. 2018 Mar 1;43(5):1115-1118. doi: 10.1364/OL.43.001115.
Planar laser-induced fluorescence (PLIF) of hydroxyl (OH) and formaldehyde (CHO) radicals was performed alongside stereo particle image velocimetry (PIV) at a 20 kHz repetition rate in a highly turbulent Bunsen flame. A dual-pulse burst-mode laser generated envelopes of 532 nm pulse pairs for PIV as well as a pair of 355 nm pulses, the first of which was used for CHO PLIF. A diode-pumped solid-state Nd:YAG/dye laser system produced the excitation beam for the OH PLIF. The combined diagnostics produced simultaneous, temporally resolved two-dimensional fields of OH and CHO and two-dimensional, three-component velocity fields, facilitating the observation of the interaction of fluid dynamics with flame fronts and preheat layers. The high-fidelity data acquired surpass the previous state of the art and demonstrate dual-pulse burst-mode laser technology with the ability to provide pulse pairs at both 532 and 355 nm with sufficient energy for scattering and fluorescence measurement at 20 kHz.
在高度湍流的本生火焰中，以20kHz的重复频率，同时进行了羟基（OH）和甲醛（CHO）自由基的平面激光诱导荧光（PLIF）以及立体粒子图像测速（PIV）测量。一台双脉冲猝发模式激光器产生用于PIV的532nm脉冲对包络以及一对355nm脉冲，其中第一个用于CHO的PLIF。一个二极管泵浦固态Nd:YAG/染料激光系统产生用于OH PLIF的激发光束。这些组合诊断技术产生了OH和CHO的同步、时间分辨二维场以及二维三分量速度场，便于观察流体动力学与火焰前沿和预热层之间的相互作用。所获取的高保真数据超越了先前的技术水平，并展示了双脉冲猝发模式激光技术能够在532nm和355nm处提供具有足够能量的脉冲对，以在20kHz下进行散射和荧光测量。
