Numerical investigation of Weber number and gravity effects on fluid flow and heat transfer of successive droplets impacting liquid film  

作　　者：WANG JiXiang QIAN Jian CHEN Xia LI EnHui CHEN YongPing 

机构地区：[1]College of Electrical,Energy and Power Engineering,Yangzhou University,Yangzhou 225009,China [2]Department of Mechanical and Aerospace Engineering,The Hong Kong University of Science and Technology,Hong Kong 999077,China [3]Jiangsu Key Laboratory of Micro and Nano Heat Fluid Flow Technology and Energy Application,School of Environmental Science and Engineering,Suzhou University of Science and Technology,Suzhou 215009,China [4]Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education,School of Energy and Environment,Southeast University,Nanjing 210096,China [5]Beijing Institute of Electronic Engineering,Beijing 100854,China

出　　处：《Science China(Technological Sciences)》2023年第2期548-559,共12页中国科学（技术科学英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant Nos.52106114,51725602,and 52036006)。

摘　　要：Droplet-based high heat flux dissipation technique under multi-gravitational environments has gained increasing research attention due to the increased requirements of heat dissipation in advanced air-/space-borne electronics.In this paper,a threedimensional model was developed to investigate the impact of continuous droplets on liquid film under various Weber numbers and gravity loads.In other words,the effects of Weber number and gravity load on the flow and heat transfer characteristics were investigated.The results demonstrated that the dissipated heat flux was positively correlated with both Weber number and gravity load.A large Weber number indicated larger kinetic energy of a droplet,leading to a greater disturbance on the impacted film area.When the Weber number was doubled,the average wall heat flux could be enhanced by 36.3%.In addition,the heat flux could be boosted by 5.4%when the gravity load ranged from 0 to 1g.Moreover,a weightless condition suppressed the vapor escape rates on the heating wall where the volume fraction of the vapor on the wall could increase by 20%under 0g,leading to deteriorated heat transfer performance.The novelty in this paper lies in the accurate three-dimensional modeling of an aerospaceoriented droplet impacting two-phase heat transfer and fluid dynamics,associating macro-scale thermal performance to microscale thermophysics mechanisms.The findings of this study could guide the development of aerospace-borne spray cooling facilities for advanced aerospace thermal management.

关 键 词：multiple droplets impact phase-change heat transfer multiphase fluid dynamics WEIGHTLESSNESS hyper-gravity 

分 类 号：O35[理学—流体力学]