Numerical Modeling of Isolated Oxygen Droplet Evaporation in Steam. A First Approach.

Kurzfassung

The problem of non-equilibrium boundary conditions on an evaporating liquid oxygen (LOX) droplet is considered. Temperature and concentration jumps were used to describe the kinetic effects on the droplet surface under high ambient temperature. The properties of these jump formalisms were analyzed and the possibility of its employment in a numerical study of evaporation in a LOX/H2O system investigated. With these conditions the numerical modeling of quasi-stead evaporation of LOX in stagnant steam was carried out: drop lifetimes and analytical solutions for temperature and concentrations distributions in the vicinity of evaporating droplet are derived. The coefficients of temperature and concentration jumps demonstrate great sensitivity to thermophysical properties of the system. The results show that the implied boundary conditions are valid for the modeling of evaporation especially in systems with very questionable equilibrium conditions on the phase boundary.