Product Code: ICA10_P 2

Laser Ignition of Combustion Engines for Cleaner Vehicles (Plenary)
Authors:
Takunori Taira, Laser Research Center for Molecular Science; Okazaki Japan
Presented at ICALEO 2010

A great deal of effort has been made on the laser ignitions for an ideal combustion engine. Unfortunately, it seems to be limited as a basic issue because the conventional highly brightness giant pulse solid-sate lasers are not suitable for vehicle mobile applications. Recent Micro Solid-State Photonics, which includes the field of transparent laser ceramics with controlled micro-domain structure, is making an impact in the development of high-brightness microchip solid-state lasers. In our passively Q-switched Nd:YAG/Cr:YAG microchip laser, the output energy of 3 mJ per pulse was obtained with the optical-to-optical efficiency of 19 %. The brightness of the sub-ns and diffraction limit pulse microchip laser was calculated to be >0.3 PW/sr-cm2 and the optical power intensity of >5 TW/cm2 was estimated at the focal point. By the sophisticated laser operation of a five-pulse train, a 100 %-ignition was successfully demonstrated in a lean mixture of an A/F 17.2, where spark plug ignition failed. Finally, ignition tests for a real vehicle engine were performed. These kinds ceramic microchip lasers should be desirable, compact, and reliable laser sources as Giant Micro-Photonics for clean vehicles engine directly. Even if for the electric vehicles, the potential advantages of the electric power generations (cogeneration, nuclear system, and so on) will contribute the clean systems in future.