Laser Applications to Turbulent Reactive Flows:Density Measurement by Resonance Absorption and Scattering Techniques.

摘要

A study of the feasibility of applying resonance absorption and scattering techniques for the measurement of species densities in turbulent reactive flows is presented. Light interaction -- including Mie, Rayleigh, and Raman scattering, resonance absorption, and resonance scattering -- is first discussed. Resonance absorption and scattering cross sections in the ir, visible, and uv spectral regions are estimated for selected atomic and molecular species. A brief survey of tunable lasers and photodetectors is given. Application of resonance absorption and scattering to fluid species densities measurement, including consideration of signal-to-noise ratio, minimum detectable number densities, and some experimental results, is discussed. Comparisons of various laser density diagnostic techniques and their advantages and limitations are also given. It is concluded that these techniques are applicable for a simple chemical system and can be used to study turbulent reactive flow phenomena. For a more complex chemical system, spectroscopy and quenching data are needed in order to evaluate feasibility.