老化效应对涂层表面池沸腾传热性能的影响  

Effect of Aging Effect on Boiling Heat Transfer Performance of Coating Surface

作　　者：钟达文 廉学新 史昊鹏 韩昱程 ZHONG Dawen;LIAN Xuexin;SHI Haopeng;HAN Yucheng(Beijing Key Laboratory of Passive Nuclear Power Safety and Technology,North China Electric Power University,Beijing 102206,China)

机构地区：[1]华北电力大学北京市非能动核能安全技术重点实验室,北京102206

出　　处：《原子能科学技术》2024年第1期93-102,共10页Atomic Energy Science and Technology

基　　金：国家自然科学基金(51706068);北京市自然科学基金(3192035);中央高校基本科研业务费(2020MS034)。

摘　　要：压力容器外部冷却(ERVC)是第三代压水堆核电站严重事故缓解策略的关键技术,其表面临界热流密度(CHF)决定了压力容器的完整性。为探究压力容器真实材料SA508钢表面老化对涂层表面CHF特性的影响,开展了SA508钢光表面和基于SA508钢的TC4钛合金多孔涂层表面在不同老化状态下的沸腾换热特性实验研究。结果表明:SA508钢光表面在水中会快速氧化,随着老化的加深,其CHF呈上升趋势,上升幅度在20%以内;CHF增强的原因在于SA508钢氧化生成了能改善表面润湿性的Fe3O4磁性微纳米颗粒层。随着氧化的加深,TC4涂层表面由超亲水特性变为疏水特性,基体SA508钢生成的氧化物易堵塞涂层孔隙,CHF呈恶化趋势。External reactor vessel cooling(ERVC)is a key technology in the severe accident mitigation strategy of third generation pressurized water reactor nuclear power plants,and the critical heat flux(CHF)determines the pressure vessel integrity.Studies on ERVC boiling heat transfer enhanced by coating show that coating surface can significantly increase CHF,in order to investigate the aging effect of the real material of nuclear reactor pressure vessel SA508 steel surface on CHF characteristics of coating surfaces,experimental studies on boiling heat transfer characteristics of SA508 steel bare surface and TC4 titanium alloy porous coating surface based on SA508 steel under different aging conditions were carried out.The substrate of SA508 steel bare surface was made of copper block and 3 mm thick SA508 steel by explosive welding.The TC4 titanium alloy porous coating surface was prepared by spraying particles on the bare surface of SA508 steel by supersonic cold gas spray technology.The micro-scale(the diameter of particles is 10-50μm)TC4 titanium alloy particles were accelerated to a high speed of 400-500 m/s by the propulsion from a stream of high-pressure inert gases with a much lower temperature than thermal spraying.Four kinds of aging experiments were carried out on the SA508 steel bare surface and three kinds of aging experiments on the TC4 titanium alloy porous coating surface at the inclination angle of 5°.The results show that the SA508 steel bare surface oxidizes rapidly in water,and the CHF tends to increase with the deepening of aging,within 20%.The scanning electron microscopy and EDS characterization were used to analyze the surface characteristic.The CHF enhancement is due to the generation of Fe 3O 4 magnetic micro-nano particle layers that improve surface wettability and added the nucleation sites by oxidation of SA508 steel.Nevertheless,the CHF increase due to oxidation is limited.Compared with the SA508 steel bare surface,the CHF of TC4 coating surface without oxidation increases more than 36.9%.T

关 键 词：相变 传热 涂层 沸腾换热 临界热流密度 氧化 

分 类 号：TL33[核科学技术—核技术及应用] TQ026.4[化学工程]