化工进展2023，Vol.42Issue(12)：6171-6179,9.DOI:10.16085/j.issn.1000-6613.2023-0172
纳米孔链双层复合表面过冷池沸腾传热特性
Heat transfer characteristics of subcooled pool boiling on two-layer composite surface with nano-porous chain
摘要
Abstract
The heat transfer enhancement of phase change by composite porous structure is an important topic in the fields of energy and chemical industry.Based on the concept of vapor-liquid synergetic transport,two-layer hierarchical structure nested with two-dimensional nano-porous chain on the silicon substrate was processed by femtosecond laser orthogonal scanning method.The subcooled pool boiling heat transfer performance of the porous structure was experimentally investigated.The experimental medium was HFE-7100.Compared with a smooth surface,the wall superheat of the two-layer porous structure at the onset of nucleate boiling was reduced from 16.7K to 12.3K at liquid subcooling of 35K,and the ratio is 26.3%.The maximum critical heat flux was increased by 128.7%.At the same time,the enhancement mechanism of boiling heat transfer was studied by observing bubble behaviors with a high-speed camera.It was found that a large number of interconnected cavities formed on the surface and inside the porous structure increase the effective nucleation site density.And nano-pores and two-layer structure provided vertical and horizontal liquid replenishment.The bubble size was smaller,and the departure frequency was faster under high heat flux.The increased nucleation site density and the vapor-liquid synergetic transport enhanced the micro convection and the thin liquid film evaporation,which effectively enhanced the boiling heat transfer coefficient and critical heat flux.关键词
双层多孔结构/过冷池沸腾/相变/传热/气液协同输运/气泡Key words
two-layer porous structure/subcooled pool boiling/phase change/heat transfer/vapor-liquid synergetic transport/bubble分类
能源科技引用本文复制引用
石尔,易苹,赵斌,汪琼,张成云..纳米孔链双层复合表面过冷池沸腾传热特性[J].化工进展,2023,42(12):6171-6179,9.基金项目
国家自然科学基金(11974085) （11974085）
湖南省教育厅创新平台开放基金(20K002) （20K002）
湖南省研究生科研创新项目(CX20210799). （CX20210799）
