摘要
通过环向加热营造辐射热增益加热条件,采用PIV粒子图像测速法研究升温速率和高径比对全浮区液桥稳态热毛细对流流场时空演化、横/纵向速度的影响规律。研究结果表明,当上/下半浮区理查森数差值的绝对值|ΔRi|增大时,上半浮区胞元流对下半浮区胞元流侵占加剧,导致下半浮区胞元流被抑制于近自由界面附近;随着升温速率的提高,由于上半浮区体回流作用显著,流动方向与辐射换热引发的流体导热方向相反。加之界面流流动换热增强,体回流携带的冷流体迅速补充至自由界面,导致上半浮区温差逐渐增加。此外,液桥高径比的增加能够促使液桥上半浮区胞元流涡核上移,提升下半浮区温差,促进下半浮区胞元流发展,提升下半浮区界面流速度。
This paper investigates the radiative heat gain heating conditions created through circumferential heating.Utilizing Particle Image Velocimetry(PIV),the experimental study examines how heating rate and aspect ratio influence the spatiotemporal evolution of the steady-state thermocapillary convection within the liquid bridge’s full floating zone,as well as the transverse and longitudinal velocity distributions.Results indicate the intrusion of the upper zone’s cellular flow into the lower zone intensifies as the absolute difference in the Richardson number between the upper and lower floating zones(|ΔRi|)increases,suppressing the lower zone’s cellular flow near the free interface.Because the bulk return flow in the central region of the upper floating zone becomes more pronounced with the rise of the heating rate,the flow direction is opposite to the conductive heat transfer induced by radiative heat exchange.Meanwhile,as the interfacial convective heat transfer intensifies,the cold fluid carried by the bulk return flow rapidly replenishes the interface,resulting in a progressive increase in the temperature difference within the upper floating zone.Moreover,an increase in the aspect ratio of the liquid bridge promotes the upward movement of vortex cores in the upper floating zone’s cellular flow and enhances the temperature difference in the lower zone,thus facilitating the development of cellular flow and accelerating the interfacial flow velocity in the lower floating zone.
作者
杨硕
冯驭
吴峻冰
梁凯
刘展志
刘哲
崔洁
罗金涛
王天羽
YANG Shuo;FENG Yu;WU Junbing;LIANG Kai;LIU Zhanzhi;LIU Zhe;CUI Jie;LUO Jintao;WANG Tianyu(Key Laboratory of Liaoning for Clean Combustion Power Generation and Heating Technology,Shenyang Institute of Engineering,Shenyang 110136,China)
出处
《重庆理工大学学报(自然科学)》
北大核心
2026年第3期193-202,共10页
Journal of Chongqing University of Technology:Natural Science
基金
国家自然科学基金项目(51906163)
辽宁省科学技术计划面上项目(2021-MS-270)
辽宁省教育厅高等学校基本科研业务项目(LJ242411632102)
辽宁省科技计划联合计划(基金)应用基础研究项目(2023JH2/101700256)。
关键词
热毛细对流
全浮区液桥
辐射热增益
稳态流
thermal buoyancy-driven capillary convection
fully floating zone liquid bridge
radiative heat gain
steady-state flow
