Numerical simulation of liquid hydrogen droplets “group” evaporation and combustion

Abstract

The leakage of LH from high-pressure storage tanks will trigger a series of behaviors such as group evaporation, dispersion, and combustion. In this study, hydrodynamic model combined with point source method (PSM) were tested for the analysis of “group interaction effects” involved in LH droplets evaporation and combustion processes. Three specific arrangement array cases: binary, equilateral triangular, and five-particle array were selected. With regard to binary array, in the case of pure evaporation (T∞=300K), surface H2 mass fraction (YH2,w) is equal to 0.77 on the side near the other droplet and 0.75 on the side away from the other droplet. When combustion occurs (T∞=3000K), it takes 0.0752 s for binary droplets to finish evaporation. The flame front is located at 156 times the LH droplet radius (156 a0) away from the binary array midpoint and its temperature (Tf) can go up to 3885 K. The flame of the binary LH array changes from a common flame to two individual flames when the distance of the two droplets (l0) is equal to 364 times the droplet radius (l0=364a0). And when l0/a0 is set to 1500, interactions between the two droplets disappears completely. In the cases of equilateral triangular array and five-particle array combustion (T∞=300K), larger flames are formed due to local deficiency of oxygen. The flame front is located at 230 a0 away from the equilateral triangular array midpoint and 365 a0 away from the five-particle array midpoint, respectively.