Experimental results from a high performance Froth Singlet Oxygen Generator (FSOG)

Abstract

This paper presents the development and initial experimental testing of a new compact, high-performance singlet oxygen generator (SOG). The generator uses a centrifugal design to assist in two-phase separation, a porous plate injection technique to create a froth and maximize chlorine utilization, and a closely coupled minimum length nozzle (MLN) to minimize transport losses. A high froth speed in the curved wall region is essential in order to attain a significant centrifugal force that pins the liquid component to the curved wall, which consequently results in a rapid and efficient separation of the vapor containing the excited oxygen that then flows into the nozzle. This generator operates without diluent and was demonstrated to perform at pressures greater than 350 Torr, which enables the technology to operate without the need for a pressure recovery system in an airborne chemical oxygen-iodine laser (COIL). The implementation of this froth SOG (FSOG) in combination with the use of a MLN allows the generation of large number densities of excited oxygen at a very high plenum pressure without the use of any diluent. Experimental results for this novel FSOG, along with the engineering logic behind it, are presented. Number densities greater than 5.3×1017 cm–3 were measured via calibrated spectroscopic analysis of the O2(1 Δ) emission about 1268 nm at the exit of a supersonic nozzle. To the authors’ knowledge, the FSOG produced a higher pressure and larger excited oxygen number density than any other SOG system reported.