摘要: |
喷嘴的流量、雾化锥角、雾化粒径等是决定室外造雪机成雪过程的重要因素。针对国产室外造雪机用旋流式喷嘴,基于VOF方法和RNG k-ε湍流方程建立了雾化模型,对水在喷嘴内的雾化过程进行研究,同时分析了入口水压和喷嘴内壁面光洁度对雾化效果的影响。结果表明:雾化锥角和液膜厚度对入口压力变化的敏感性较弱;雾化粒径随入口压力的增大而减小,粒径减小的主要原因是流体速度增加,液膜不稳定性增强,增强了液滴的二次破碎;喷嘴内壁面光洁度减小,雾化产生的空气涡减小,水雾化锥角减小,但有助于获得较大的雾化流量。 |
关键词: 室外造雪机 旋流喷嘴 雾化特性 VOF |
DOI: |
投稿时间:2022-02-09 修订日期:2022-04-05
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基金项目:国家重点研发计划项目(2020YFF0303903)资助。 |
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Study of the Atomization Performance of Swirl Nozzle for Snow-making Machine |
Wu Haifeng1, Liu Jiawei1, Wang Ruixiang1, Zhang Bowen1, Xu rongji1, Yan gang2, Dong peiwen1,2, Zhang hongjun3
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(1.Beijing Engineering Research Centre of Sustainable Energy and Buildings,Beijing University of Civil Engineering and Architecture;2.Department of Refrigeration and Cryogenic Engineering of School of Energy and Power Engineering, Xi'an Jiaotong University;3.Beijing Carving Ski Group Co., Ltd) |
Abstract: |
The flow rate, spray cone angle, and droplet diameter of swirl nozzles are key parameters in the snow-making process of an outdoor snow-maker. Aimed at the swirl nozzle of a domestic outdoor snow-maker, a mathematical model was established based on the volume of fluid method (VOF) and RNG k-ε turbulence model. The atomization process for the water in the nozzle was studied, and the effects of the water injection pressure and inner wall roughness of the nozzle on the atomization performance were analyzed. The results demonstrate that the spray cone angle and liquid film thickness are less sensitive to changes in the injection pressure, while the droplet diameter decreases with the increase in injection pressure. The decrease in droplet diameter is attributed to the increased water velocity, which enhanced the instability of the liquid film and the secondary breakup of droplets. As the smoothness of the nozzle wall decreased, the air vortex and water atomization cone angle generated by atomization also decreased, however, the reduced smoothness of the nozzle is helpful to obtain a larger atomization flow rate. |
Key words: outdoor snow-maker swirl nozzle atomization characteristics VOF |