Numerical investigation on the characteristics of leakage and dispersion of cryogenic liquid oxygen in open environment

Abstract

Liquid oxygen/liquid hydrogen and liquid oxygen/liquid methane are widely used as cryogenic propellants in the field of aerospace launch. Numerical research is carried out for the potential liquid oxygen leakage caused by damage of tanks or rupture of pipelines. The Mixture multiphase flow model is used, where the slip velocity between the gas–liquid phases and the phase change of water vapor are considered. The development process of the temperature and oxygen concentration distribution after the leakage and the extinction process after the leakage stops are investigated. What's more, the influences of ambient temperature, spill rate, cofferdam, and wind direction on the temperature and concentration distribution are analyzed. The results show that, after about 90 s of continuous liquid oxygen leakage, the oxygen cloud reaches a quasi-steady state. The volume fraction of oxygen in the air reduces to 23% at 60 s after stopping the leakage. As the ambient temperature increases from 253 K to 308 K, the hazardous temperature region is reduced while the maximum oxygen concentration increases from 0.422 to 0.471. An increase in spill rate significantly increases the hazardous regions of temperature and concentration. In contrast, increasing the angle in the horizontal plane between the wind direction and the direction of leakage or building a cofferdam can reduce the extent of the hazardous region. The results of this paper can provide references for the development of liquid oxygen leakage experiments, the development of related standards, and the emergency treatment of accidents.