摘要
闪蒸喷雾冷却技术因其优异的冷却能力广泛应用于航空航天、激光医疗、电力等领域,其液滴撞击壁面后的动力学行为特性对冷却过程有重要影响。采用VOF方法对闪蒸喷雾过程中液滴撞击壁面的动力学行为进行数值模拟研究,并与常规喷雾冷却中没有闪蒸的液滴撞击壁面的形态变化进行了对比。结果表明,闪蒸喷雾冷却时液滴撞击壁面过程中会由于自身过热相变产生气泡进而断裂;当过热度或壁面温度增加、液滴直径或初始速度减小时,液滴更易断裂;液滴铺展系数随过热度、初始直径、初始速度以及壁面温度的增大而增大,当断裂发生后,铺展系数会有明显上升。
Flash spray cooling technology is widely used in aerospace,laser medical,electric power and other fields due to its excellent cooling ability,and the kinetic behavior characteristics of the droplets after impacting the wall have an important influence on the cooling process.The kinetic behavior of droplet impact on the wall surface during flash spraying was numerically simulated using the VOF method,and compared with the morphology change of droplet impact on the wall surface in conventional spray cooling without flash evaporation.The results show that the droplet impacting the wall during flash spray cooling would produce bubbles and then fracture due to its own superheated phase transition;the droplet is more likely to fracture when the superheat or wall temperature increases,and the droplet diameter or initial velocity decreases;the spreading coefficient of the droplet increases with the superheat,the initial diameter,the initial velocity,and the wall temperature,and there is a significant increase in the spreading coefficient when the fracture occurred.
作者
李星泊
魏晓净
杨庆忠
王铁营
张哲
Li Xingbo;Wei Xiaojing;Yang Qingzhong;Wang Tieying;Zhang Zhe(Tianjin Key Laboratory of Refrigeration Technology,Tianjin University of Commerce,Tianjin 300400,China)
出处
《低温与超导》
CAS
北大核心
2024年第3期64-70,共7页
Cryogenics and Superconductivity
基金
国家自然科学基金(52206274,52106106)资助。
关键词
过热液滴
闪蒸
断裂
铺展系数
Superheated droplets
Flash vaporization
Fracture
Spreading coefficient
