Output Power Enhancement of a Chemical Oxygen-Iodine Laser by Predissociated Iodine Injection

Output power enhancement of a chemical oxygen-iodine laser (COIL) by an injection of predissociated iodine was studied. Iodine molecules were dissociated into atoms by the microwave discharge prior to injection. It was determined that predissociation caused a negative effect on the output power enhancement when this technique was applied to a conventional supersonic COIL. Model calculations revealed that the existence of atomic iodine at the plenum caused the dissipation of stored energy. It was demonstrated that decreasing the mixing point pressure was crucial to obtain output power enhancement by the predissociation technique. For this purpose, a low-pressure transonic mixing scheme with a grid nozzle array was developed. A 9% enhancement of output power was demonstrated.