Experimental Study on Initiating Detonation Waves by Shock Focusing in Laser Ignition

The combination of laser-induced spark ignition and shock focusing phenomenon is proposed to generate detonation waves in a shorter distance. And, to certify the feasibility of this method, schlieren visualization of the flow field has been conducted using elliptical and rectangular cavities. The Mach number change of the shock wave and the combustion wave clarified that an overdriven detonation was initiated. And, from the comparison with the schlieren images, the initiation occurred at the center line where two combustion waves and an incident shock wave collide.