Recent Work on the Development of an Electric Discharge Oxygen Iodine Laser

Theoretical studies have indicated that sufficient fractions of O ₂(¹δ) may be produced in an electrical discharge that will permit lasing of an electric discharge oxygen-iodine laser (ElectriCOIL) system in conjunction with injection of pre-dissociated iodine. Results of those studies along with more recent experimental results show that electric excitation is a very complicated process that must be investigated with advanced diagnostics along with modeling to better understand this highly complex system. In this paper, recent work in the development of the ElectriCOIL system is discussed. A kinetic package appropriate for the ElectriCOIL system is presented and implemented in the detailed electrodynamic GlobalKin model and the Blaze II laser modeling code. A parametric study with the Blaze II model establishes that it should be possible to attain positive gain in the ElectriCOIL system, even with subsonic flow. The Blaze II model is in reasonable agreement with early gain data. Temperature is a critical flow variable, especially in the subsonic cases. Simulations of a supersonic ElectriCOIL system indicate that significant performance levels can be attained, even at low yield levels of 20% or less. In addition, pre-dissociation of the iodine is also shown to be very important for the supersonic flow situation. Given the critical nature of the temperature issue, it appears that supersonic flow will be required for the ElectriCOIL system to achieve significant performance levels, but these simulations also indicate that it should be possible to demonstrate a subsonic system.