Ignition Characteristics of GH2/GOx Mixture Using Laser Ablation Ignition

The characteristics of a laser ablation igniter were investigated systematically. This kind of igniter is expected to realize a lightweight rocket engine system that consists of many combustion chambers, such as the Reaction Control System (RCS), without having heavy spark igniters. In this igniter, ignition is accomplished utilizing a high-temperature metal vapor produced by focusing a high-intensity laser pulse transmitted through an optical fiber. The laser ablation igniter was tested in a GH2/GOx thruster (dia. 1 cm). As a result, the minimum ignition energy was found to be lower than 2 mJ, and the required ignition energy decreased with increasing pressure in the combustion chamber.