常重力倾角下的浮力-热毛细对流转捩特性研究  

Study of transition characteristics of buoyancy-thermocapillary convection under the gravitational tilt

作　　者：杨硕 王宇航 高宇 葛璞石 罗金涛 李万琪 郑云一 YANG Shuo;WANG Yuhang;GAO Yu;GE Pushi;LUO Jintao;LI Wanqi;ZHENG Yunyi(Key Laboratory of Liaoning Province for Clean Combustion Power Generation and Heating Technology,Shenyang Institute of Engineering,Shenyang 110136,China)

机构地区：[1]沈阳工程学院辽宁省洁净燃烧发电与供热技术重点实验室,沈阳110136

出　　处：《重庆理工大学学报(自然科学)》2025年第1期195-204,共10页Journal of Chongqing University of Technology:Natural Science

基　　金：国家自然科学基金项目(51906163);辽宁省科技计划基金项目(2022-MS-304);辽宁省教育厅高等学校基本科研业务项目(先导计划创新发展项目)(LJ242411632102);辽宁省科技计划联合计划(基金)应用基础研究项目(2023JH2/101700256);辽宁省教育厅高校基本科研项目(重点攻关)(LIKZZ20220138);沈阳市科技项目(RC210010,22-322-3-20)。

摘　　要：残余加速度引起的流体晃动/倾斜是空间材料制备中常见的影响因素。该研究利用配备近焦镜头的高速摄像机和自行开发的液桥界面识别软件包,研究重力倾斜角对浮力-热毛细对流的影响。结果表明,受重力倾角影响的浮力-热毛细对流仍然经历了由稳态流至振荡流的时空演化。在稳定浮力-热毛细对流阶段,由于左、右界面曲率的不平衡,导致胞元流涡核畸变使胞元流靠近自由表面,并收缩至中间高位置处。随着重力倾角的增大,横/纵向速度峰值明显降低,与无重力倾斜角相比,速度峰值衰减了约26%~27%。自由界面处纵向速度梯度显著增大。因此,重力倾角对提高表面流的流动速度起着重要作用。在振荡浮力-热毛细对流阶段,左、右胞元发生周期性侵占。涡核位置靠近热/冷角自由界面处,振荡浮力-热毛细流受到明显抑制,临界温差提高约25%,热角区温度振荡发启时间延迟。Fluid slosh/gravitational tilt caused by residual acceleration in microgravity is common in space material preparation.In this paper,the effect of gravitationaltilt on the buoyancy-thermocapillary convection is studied by employing a high-speed camera equipped with a near focus lens and a self-developed interface image recognition package for liquid bridge interface recognition.Our results show the buoyancy-thermocapillary convection under the influence of gravitational tilt still presents the space-time evolution from steady and oscillatory flow.In the stage of stable buoyancy-thermocapillary convection due to the imbalance of the left and right interfaces curvature,the vortex core distortion makes the cell flow close to the free surface and shrink to the intermediate height.With the increase of gravitational tilt,the peak transverse/longitudinal velocity decreases markedly with the peak velocity down by about 26%-27%compared with that of the non-gravitational tilt.The longitudinal velocity gradient at the free interface increases significantly.Therefore,the gravitational inclination plays an important role in enhancing the surface flow velocity.In the oscillatory buoyancy-thermocapillary convection,the left and right cell flows undergo periodic occupation.The vortex core is located near the free interface of the hot/cold corner,and the oscillatory buoyancy-thermocapillary convection is largely suppressed.The critical temperature difference is increased by 25%and the onset of temperature oscillation at hot corner is delayed.

关 键 词：非轴对称液桥 浮力-热毛细对流 重力倾角 

分 类 号：TK121[动力工程及工程热物理—工程热物理]