Research Projects

Laser induced incandescence represents a promising means for measuring soot particulate from diesels, gas turbine engines as well as other sources. Under the current program, the measurement sensitivity has been enhanced to also allow ambient soot particulate concentration measurements. The purpose of this program was to develop the technology into a useful portable instrument that will provide immediate time-resolved measurements of particulate emissions for a broad range of applications including diesel and gas turbine engine development, evaluation of particulate control systems, and help evaluate compliance to particulate emissions regulations. During this effort, a NIST traceable calibration method was developed and refined to improve the reliability and to better define the instrument response to soot. At the same time, optical systems were developed to produce a more compact instrument which was thoroughly tested for operational integrity under typical industrial environments. Software was developed that included algorithms to fully automate the instrument set up functions and to automatically track the soot concentrations over a range of one million to one. The earlier LII 200 version was evaluated and tested at our industrial partners sites. As a result of these tests, several improvements were defined and implemented. From these results, a next generation LII 300 instrument evolved which is much more compact, has greater sensitivity and is easier to operate. Measurement comparisons to made with gravimetric results showed excellent agreement.