Development of Fuel Droplet Vaporization Rate Measurement Techniques for Realistic Burning Spray Applications

Abstract

Technology to support design for the next generation of aircraft fuel injectors is being developed by NASA’s Fundamental Aeronautics Program to reduce emissions, increase efficiency, and enable fuel flexible aircraft. The design of these fuel injectors can be aided by measuring the vaporization rates of jet fuel droplets in realistic, burning sprays. Currently, in this environment, no instantaneous vaporization rate measurement techniques have been applied. After surveying techniques for potential development for this application, two techniques were identified: stimulated Raman scattering (SRS) and droplet lasing spectroscopy (DLS). Plans were developed for the modification of these techniques for this specific application. Developments of the SRS technique were tested including measurement of a water droplet diameter change rate. SRS spectra were also collected from jet fuel droplets.