摘要
热盐驱动下的扩散对流现象是海洋中高纬度海域普遍存在的一种现象,对其进行数值模拟可更细致地研究海洋小尺度动力过程。文章分析了扩散对流的形成机制,建立了二维方腔模型,通过有限体积法求解控制方程,对其分层现象进行了数值模拟。研究给出了流场的温度及盐度随时间演化的关系,展现了流场中速度的涡旋结构,分析了温盐台阶结构的生成、合并的演化过程,并对其物质和能量的输运进行了初步的理论解释。另外,对不同热流密度情况下的扩散对流现象进行了对比研究,发现随着热流密度的增加,台阶结构的演变速率变快,而且上边界冷却对其演化速率具有促进作用,但热流密度的改变并没有对台阶结构的演变趋势产生明显的影响。
Diffusive convection driven by temperature and salinity is a ubiquitous phenomenon in the mid and high latitudes of the ocean. Numerical simulation of diffusive convection can be used to study small-scale dynamic processes of the ocean. In this study, we analyze the formation mechanism of diffusive convection and establish a two-dimensional cavity model. The governing equation of the model is solved by the finite volume method, and the process of layering phenomenon is simulated numerically. The temporal evolution of temperature and salinity of the flow field is given, and the vortex structure of the velocity field is simulated. The processes of the formation and merging of diffusive convection staircases are analyzed, and a theoretical explanation for mass and energy transport processes is given. In addition, the diffusive convection under different heat flux density is discussed. It is found that the growth rate of diffusive convection staircases increases with the increase of heat flux density, and the cooling from the upper boundary plays an important role in accelerating its growth. The variation of heat flux density does not have a significant impact on the evolution of diffusive convection staircases.
作者
徐岩
刘香全
宋仁刚
岑显荣
郭双喜
周生启
XU Yan;LIU Xiangquan;SONG Rengang;CEN Xianrong;GUO Shuangxi;ZHOU Shengqi(College of Electronic,Communication and Physics,Shandong University of Science & Technology,Qingdao 266590,China;State Key Laboratory of Tropical Oceanography (South China Sea Institute of Oceanology,Chinese Academy of Sciences),Guangzhou 510301,China;State Key Laboratory of Integrated Optoelectronics,Institute of Semiconductors,Chinese Academy of Sciences,Beijing 100083,China;College of Materials Science and Optoelectronic Technology,University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《热带海洋学报》
CAS
CSCD
北大核心
2019年第1期11-18,共8页
Journal of Tropical Oceanography
基金
国家自然科学基金项目(11547037
11604181
41706029
41776033)
广东省自然科学基金项目(2016A030311042
2016A030313155)
热带海洋环境国家重点实验室(中国科学院南海海洋研究所)开放基金资助课题(LTO1710)~~
关键词
扩散对流
温盐台阶
盐度
温度
diffusive convection
numerical simulation
salinity
temperature