An important aspect of rocket engine testing is engine wear. One method that has been used to monitor for rocket engine wear is atomic emission in the UV-visible region from metal species in the plume. An alternative method that offers the promise of increased sensitivity and spatial resolution is laser-induced breakdown spectroscopy. This method uses atomic emission from a micro-plasma formed at the focus of a high peak power laser. It uses gated-detection with a fixed delay after the laser pulse. This has the advantage of discriminating against background emission in the plume. Also the laser micro-plasma has a higher temperature than the plume, which increases atomic emission strength. During Phase I a LIBS system will be developed and demonstrated on several hydrocarbon-fuel flames and test stands. It will be optimized for sensitivity. Its capabilities, including detection limits and spatial resolution, will be characterized and reported. At the end of Phase II a working prototype will be completed and fully tested. Potential Commercial Application(s): In addition to being a monitor for rocket engine wear, the LIBS system can be used to monitor automobile engines for metal species in the exhaust. This would be useful for monitoring engine health as well as monitoring for toxic metals released in the atmosphere as pollutants. A similar application for jet engines is apparent.
