Abstract - Dunn-Rankin This is an industry-university cooperative research project between the University of California at Irvine and Metro Laser of Irvine, CA. Resonant holographic interferometry (RHI) is a laser-based diagnostic that combines the three-dimensional imaging capability of holography, the phase- sensitive detection of interferometry, and the species specificity of resonance spectroscopy. It accomplishes this by recording two simultaneous holograms at two different wavelengths, one tuned near an absorption line and the other tuned off this feature. Upon reconstruction, the resulting interference fringes correspond uniquely to the density of the species under interrogation while phase contributions from background species, thermal and pressure instabilities and optical aberrations are subtracted out. The approach has been successfully demonstrated in gas-phase combustion systems. In this effort, RHI is applied to multiphase systems for the first time. Specifically, products from droplet and spray combustion systems will be analyzed quantitatively. Now intrusive optical diagnostic techniques are commonly used in study of gas-phase combustion systems and other reacting flow systems. These methods are also being considered for incorporation in active control systems. However, most such techniques are limited to single-phase systems, making them unsuitable for many important combustion systems that use liquid fuels. It is speculated that RHI can overcome this hurdle.
