Development of a Photonic Crystal Fiber Delivery System for Laser Ignition in Engines

摘要

We report the use of hollow core kagome lattice Photonic Crystal Fibers (PCFs) for fiberoptic delivery of laser induced sparks and engine ignition. Beam quality characterizations of the kagome fiber using 1064 nm light showed near single-mode output with M~2=1.2 at low power and M~2=1.4 at high power. High power characterizations showed maximum pulse energy (before onset of damage) of 12 mJ for pulse durations of 12 ns, and 30 mJ for pulse durations of 30 ns. These energies should be sufficient for laser ignition of even lean fuel-air mixtures. Finally, we have developed an initial prototype of a practical laser delivery system using 3 m length of coiled kagome fiber. We have demonstrated operation of a gasoline diesel injection (GDI) single-cylinder engine with 100% ignition reliability and coefficient of variation of the indicated mean effective pressure of 1.84%.