Vaporization of Liquid Oxygen (LOX) Droplets in Hydrogen and Water Environments under Sub- and Super-Critical Conditions

Abstract

This article presents a comprehensive numerical analysis of liquid oxygen (LOX) droplet vaporization in quiescent hydrogen and water environments over a broad range of ambient conditions. The theoretical formulation is based on a complete set of conservation equations of mass, momentum, energy, and species concentrations in a spherically symmetric coordinate. A self-consistent and efficient method for evaluating transport properties and a unified treatment of general fluid thermodynamics are incorporated into an implicit finite-volume numerical scheme. The analysis is further equipped with a water-vapor condensation model for treating the phase change near the droplet surface. The effects of the Dufour and Soret cross-diffusion terms are explored and found to exert negligible influences on the droplet lifetime. Various issues associated with high-pressure droplet vaporization are investigated. In addition, correlations for droplet lifetimes are established for both LOX/hydrogen and LOX/hydrogen/water systems in terms of the initial droplet diameter, reduced critical temperature of oxygen, and thermal conductivities of oxygen and ambient gases.

Keywords:

• Irreversible thermodynamic theorem
• Subcritical and supercritical droplet vaporization
• Water vapor condensation

Additional information

Notes on contributors

Hua Meng

Current address for Prof. Hua Meng, Center for Engineering and Scientific Computation and College of Computer Science, Zhejiang University, Hangzhou, Zhejiang 310027, P.R. China. E-mail: [email protected]