Researchers in the CSU Center for Laser Sensing and Diagnostics (CLSD) have made a significant contribution to the field of laser ignition of engines by developing a new technique based on combining two laser pulses with different wavelengths. The approach has the potential to provide more efficient and cleaner combustion for both stationary and vehicular engines. The findings were recently published in the journal Nature – Scientific Reports, which should provide high visibility for the work.
In the combustion field, major emphasis has been placed on developing innovative approaches to cold and lean burn combustion. The CLSD saw the need for improvement and strategized a method to innovatively utilize laser ignition to further advance the field.
Two lasers are better than one
As a starting point, the team focused on the idea of using laser-generated sparks as an alternative source of ignition, a topic that has been significantly researched in the last 20 years. The study took this concept a step further and introduced a novel technique based on the overlap of two laser pulses that operate a different wavelengths, one ultraviolet and one near-infrared. Combining the wavelengths allows for a superior ignition source due to fundamental differences in laser plasma formation, ensuing flow-fields and combustion. The results show promise for practical combustion devices including stationary gas engines, aero-turbines, and potentially scramjet engines and rockets.
The research team
The research was performed by Azer Yalin and his CLSD research team, part of the CSU Energy Institute. The research group specializes in developing laser sensors and diagnostics for atmospheric science, combustion, and plasma applications, and has received funding from industry as well as diverse agencies including the National Science Foundation, Department of Energy, U.S. Department of Agriculture, and the Air Force.
Ciprian Dumitrache, formerly a Ph.D. student in the group and currently a postdoctoral fellow, was instrumental to executing the research. During his studies, Dumitrache was awarded the prestigious “Gordon C. Oates” Airbreathing Propulsion Award by the American Institute of Aeronautics and Astronautics, as well as a departmental teaching fellowship. When asked about the research, Dumitrache said, “The most important aspect of the research conducted at CLSD on laser ignition is that it brings together expertise from so many different fields, such as plasma physics, laser diagnostics, combustion chemistry and high-speed fluid dynamics.”