连铸喷嘴气路加速环对喷嘴出口处液相运动与分布的影响

为获得更好的高速连铸二冷区铸坯冷却效果,本文提出在气-水雾化喷嘴气路通道内增设加速环装置。根据生产工艺条件,利用Fluent软件建立了优化前后气-水雾化喷嘴的三维气-液两相流模型,分析了喷嘴进水压力和进气压力对喷嘴出口处液相速度和液相体积分数分布的影响。结果表明,本文计算条件下,当喷嘴进水压力一定时,随着进气压力的增加,喷嘴出口处液相速度显著增大,液相体积分数呈减小趋势;当喷嘴进气压力一定,随着进水压力的增加,喷嘴出口处液相速度减小,液相体积分数整体呈增大的趋势;相同工况条件下,喷嘴气路设置加速环后,喷嘴出口处的液相速度分布较优化前更稳定,液相分布均匀性得到改善。

Effects of acceleration ring in air passage of continuous casting nozzle on the movement and distribution of liquid phase at nozzle outlet

For better cooling effect of the slab in the secondary cooling zone of high-speed continuous casting, this paper has proposed to adopt an acceleration ring device in the air passage of the gas-water atomizing nozzle. According to the process conditions in production, a three-dimensional gas-liquid two-phase flow model of the nozzle before and after optimization was established by using Fluent software. The effects of nozzle inlet pressure of water and air, respectively, on the liquid-phase velocity and volume fraction distribution at the outlet before and after nozzle optimization were analyzed. The results show that under the condition of constant inlet water pressure, as the inlet gas pressure increases, the liquid-phase velocity at the nozzle outlet increases significantly, and the liquid-phase volume fraction decreases. When the nozzle inlet gas pressure is constant, with the increase of inlet water pressure, the liquid-phase velocity at the nozzle outlet decreases, and the liquid-phase volume fraction generally increases. Under the same working conditions, after an acceleration ring is adopted in the nozzle gas path, the liquid velocity distribution at nozzle outlet is more stable than that before optimization, and the liquid-phase distribution uniformity is therefore improved.