Experimental Results of a Vortex Tube Air Separator for Advanced Space Transportation

Abstract

Vortex tubes have the potential to be utilized in a compact air separation system that can extract and liquefy oxygen for many purposes, including onboard propellant generation for rocket vehicles. A theoretical and experimental investigation of the operating conditions of a two-phase flow vortex tube is being carried out to determine means to improve its air separation capabilities. Theoretical modeling indicates vortex tube performance may reach 90% oxygen purity at 90% yield. An experimental program has been initiated to provide calibration data for the theoretical modeling and to investigate the multitudes of factors involved with the vortex tube air separation process. Experiments with vortex tubes having taper angles ranging from 0o to 6o have been carried out with mixed-phase air at flow rates up to 3000 SLM. Oxygen purities of 60% at yields of 20% have been demonstrated in preliminary experiments and some of the essential operating characteristics of a two-phase flow vortex tube have been identified.