Engineering Research Equipment Grant: Simultaneous UV Raman and Fluorescence Imaging in Turbulent Diffusion Flames

同时，通过拉曼散射和紫外准分子激光诱导的荧光，用增强电荷耦合数码相机在湍流扩散火焰中对燃料、空气和反应中间体进行瞬时成像。成像技术是基于拉曼散射和激光诱导预解离荧光（LIPF）使用紫外准分子激光的最新进展。图像可以评估有限速率化学效应-燃料和空气梯度对湍流火焰化学的影响。这些有限速率的化学效应决定了火焰的燃烧效率和污染的形成。从这些图像中，湍流扩散火焰中的有限速率化学可以被量化，从而可以改进湍流-化学相互作用的计算机模型。本研究的目的是利用窄带准分子激光对拉曼光谱和荧光光谱信号进行成像，获得用于测量湍流扩散火焰中温度梯度、混合分数和次要物质（OH）的成像设备。用于点测量的光电倍增管将被门控强化（ICCD）相机所取代。

Simultaneous, instantaneous images of the fuel, air, and reaction intermediates will be made with an intensified charge-coupled digital camera in a turbulent diffusion flame by Raman scattering and fluorescence induced with an ultraviolet(UV) excimer laser. The imaging technique is based on recent advances in Raman scattering and laser-induced predissociative fluorescence (LIPF) using UV excimer lasers. The images can assess finite rate chemistry effects - the effect of gradients of fuel and air on the chemistry of the turbulent flame. These finite-rate chemistry effects determine combustion efficiency and pollution formation in flames. From the images, the finite-rate chemistry in turbulent diffusion flames can be quantified so that computer models of turbulence-chemistry interactions can be improved. This proposal is to acquire the imaging equipment necessary to measure the gradients of temperature, mixture fraction, and minor species (OH) in a turbulent diffusion flame by imaging Raman and fluorescence signals from a narrowband excimer laser. The photomultiplier tubes used in the point measurements would be replaced by a gated intensified (ICCD) camera.