Numerical simulation of the head-on collision of binary equal-sized seawater droplets was conducted by volume of fluid method for tracking the interface and an adaptive mesh for improving the calculation efficiency. In order to reveal the mechanism and the influence factors of seawater droplets in Impinging Seawater Shower Cooling Tower (ISSCT.), veracity of the numerical models was firstly validated with the experimental results of Qian. These outcomes were in good agreement with the experiments. The binary collisions of equal-sized droplets were investigated at various Weber numbers and impact parameters at room temperature and pressure conditions. The Weber number ranged from 0.5 to 200 and the impact parameters ranged from 0 to 1, which covered three different types of outcomes: coalescence, head-on separation and off -centre separation. The results show that the critical Weber number of head-on collisions between coalescence and reflexive separation is 22. The We-x schematic of various collision regimes of seawater droplets is obtained.
adaptive mesh, droplet collision, seawater, VOF method
The financial support of the Nation Natural Science Foundation of China (grant no. 51879154 and 51806128) is acknowledged.
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