摘要
为研究双扩散对流过程中流体黏性对通量的影响,本文设计了梯度浓度的双扩散试验,流体黏度随着浓度的增大而增大。在设计有中间挡板的试验水箱中注入根据糖盐组分质量分数精确配制的溶液,以控制盐指型密度稳定比在1.073,扩散型密度稳定比在0.93。移开挡板后,水箱内会形成静止状态的糖盐双层系统。为了更精确地评估双扩散现象并最小化误差,试验设置了3种时间段的双扩散试验,分别为300 s、600 s和1800 s。试验发现:短时间内通量会受黏度影响而显著减小,但随着时间的增长,这些影响被继发的扩散通量所掩盖。盐指型和扩散型双扩散的糖通量与黏度之间均存在非线性关系,在扩散型双扩散中通量比γ^(*)与黏度比之间拟合得出两者呈幂律关系;而盐指型通量比γ与黏度比之间的变化则相对复杂,需要更精细化研究。
To investigate the impact of fluid viscosity on flux during double-diffusive convection,a gradient-concentration double-diffusion experiment was designed,where viscosity increases with concentration.Precisely formulated sugar-salt solutions based on mass fraction were injected into a test tank equipped with an intermediate baffle,controlling the salt-fingering density stability ratio at 1.073 and the diffusion-dominated density stability ratio at 0.93.After removing the baffle,a stationary sugar-salt two-layer system formed within the tank.To accurately evaluate double-diffusive phenomena and minimize experimental errors,three time intervals were established for the double-diffusion tests:300 s,600 s,and 1800 s.The experimental results revealed that short-term flux is significantly reduced under the influence of viscosity.However,this effect becomes masked by subsequent diffusive fluxes as time progresses.Both salt-fingering and diffusion-dominated double-diffusion exhibit nonlinear relationships between sugar flux and viscosity.In diffusion-dominated double-diffusion,a power-law correlation was established between the flux ratioγ^(*)and viscosity ratio.Nonetheless,the discrepancy betweenγand the viscosity ratios of salt finger fluxes is relatively intricate and necessitates a more exhaustive analysis.
作者
陈铂
黄剑文
彭君可
黄升
Chen Bo;Huang Jianwen;Peng Junke;Huang Sheng(School of Hydraulic and Ocean Engineering,Changsha University of Science&Technology,Changsha 410114,China;Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province,Changsha 410114,China;Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province,Changsha 410114,China;Engineering and Technical Center of Hunan Provincial Environmental Protection for River-Lake Dredging Pollution Control,Changsha 410114,China)
出处
《海洋学报》
北大核心
2025年第8期48-54,共7页
基金
湖南省自然科学基金“双扩散对分层流界面剪切的作用机理研究”(2021JJ30704)。
关键词
双扩散对流
密度稳定比
通量比
流体黏性
double diffusion convection
density stability ratio
flux ratio
viscosity
作者简介
黄剑文(1997-),男,湖南省桂东县人,从事海洋双扩散研究。E-mail:1344280807@qq.com;通信作者:陈铂,博士,讲师,主要从事环境流体力学研究。E-mail:chenbo@csust.edu.cn。
