原子能科学技术2025，Vol.59Issue(z2)：237-244,8.DOI:10.7538/yzk.2025.youxian.0209
高温热管丝网吸液芯上碱金属钠润湿特性研究
Wetting Characteristics of Alkali Metal Sodium on Wire Mesh Wicks in High-temperature Heat Pipes
摘要
Abstract
With their compact structure,high reliability,and inherent safety,heat pipe reactors demonstrate significant potential in energy supply for deep-space,deep-sea,and remote island applications.As a critical heat transfer component in heat pipe reactors,the high-temperature sodium heat pipe relies on the wetting characteristics of sodium on the wire mesh wick.These characteristics govern the capillary-driven flow of the working fluid from the condenser to the evaporator section,thereby directly influencing the thermal performance of the system.The wetting behavior of alkali metal sodium on wire mesh wicks was systematically investigated in this study using a self-developed visualization experimental platform,which includes a sodium purification system,a temperature-and pressure-controlled argon gas system,and a visualization measurement system.Experimental results reveal that ambient pressure has minimal impact on the contact angle.Overall,at the same temperature,higher pressure leads to slightly smaller contact angles.This is attributed to the reduced surface tension between the gas and liquid phases under lower pressure due to thinner gas molecules.A consistent wetting transition temperature Ttrans(Ttrans=500℃for single-layer 600-mesh wire mesh)was observed across different pressures.Below Ttrans,the contact angle remains nearly constant(average values:128.58°,125.46°,and 113.57°under 600,800 and 1 000 Pa,respectively,with standard deviations of 2.28°,4.19°,and 7.11°).Upon reaching Ttrans,the contact angle decreases abruptly,and further temperature increases cause to drop suddenly to 0°(manifested as rapid droplet spreading).This phenomenon arises from reduced sodium surface tension at elevated temperatures and the disruption of the hydrophobic chromium oxide film on stainless steel surfaces by sodium at high temperatures,enhancing wettability.Additionally,increasing the number of wire mesh layers enlarges the contact angle,while higher mesh numbers reduce it.According to Cassie's wetting theory,the apparent contact angle is negatively correlated with the solid-liquid contact area in a material's microstructure.Higher mesh numbers increase the wire density per unit area,expanding the contact area and thus lowering the apparent contact angle.Both increasing mesh layers and mesh numbers elevate Ttrans(Ttrans for 1-layer 400-mesh,1-layer 600-mesh,and 3-layer 600-mesh wire meshes are 450,500,and 525℃,respectively).This is likely due to greater pore volume in multi-layered or high-mesh structures,which retains more residual oxygen,thereby requiring higher temperatures for sodium to reduce and disrupt the chromium oxide film.This study provides experimental insights for optimizing the design and high-precision performance analysis of high-temperature heat pipes,advancing the engineering application of heat pipe reactors.关键词
高温热管/丝网吸液芯/碱金属钠/润湿性/接触角Key words
high-temperature heat pipe/wire mesh wicks/alkali metal sodium/wettability/contact angle分类
能源科技引用本文复制引用
唐松胜,秋穗正,郭凯伦,田诗雨,孙奇士,王明军,张大林,王成龙,马誉高,田文喜..高温热管丝网吸液芯上碱金属钠润湿特性研究[J].原子能科学技术,2025,59(z2):237-244,8.基金项目
国家自然科学基金(12175219) （12175219）
四川省科技计划(2022JDRC0026) （2022JDRC0026）
中核集团"青年英才"项目 （）
