含液膜微槽的光谱反射特性模拟  

Simulation of Spectral Reflectance Properties of Microgrooves Containing Liquid Film

作　　者：路安 陈学[1] 尹斌 夏新林[1] Lu An;Chen Xue;Yin Bin;Xia Xinlin(School of Energy Science and Engineering,Harbin Institute of Technology,Harbin 150001,Heilongjiang,China)

机构地区：[1]哈尔滨工业大学能源科学与工程学院,黑龙江哈尔滨150001

出　　处：《光学学报》2025年第1期244-255,共12页Acta Optica Sinica

基　　金：国家自然科学基金(52276058)。

摘　　要：固壁表面附着液膜是工程领域中的常见现象,液膜的存在直接影响壁面的光谱反射特性。本文基于YoungLaplace方程获得液膜形貌,建立含水膜金属铜微槽结构的光谱辐射传输模型,采用时域有限差分法进行模拟分析,研究液膜厚度、槽道宽度、入射倾角以及浸润角等参数对含液膜微槽光谱反射特性的影响。结果表明,液膜显著降低了微槽结构的反射率,波长3μm处存在一个较大的吸收峰,与无液膜时相比,反射率差值达0.85。针对此类含液表面的光谱反射特性研究,液膜形状不能简化为理想的圆弧曲线。相对于槽道宽度、入射倾角,液膜厚度和浸润角引起的光谱反射率的数值波动更为明显,且两者引起的反射率差异主要体现在波长为4~10μm的区域,在该区域内的固定工况下,液膜厚度增长0.5μm,反射率下降8.94%,反射率整体随着浸润角的增大而减小,在固定工况下,浸润角在50°~120°变化时,反射率位于0.6~0.9的范围内。垂直入射时,不同工况的反射能量均集中分布于反射角为-40°~40°的中心区域内。Objective The formation of liquid films on solid wall surfaces is a common phenomenon in engineering applications,directly affecting spectral radiation characteristics.When liquid adheres to a surface,a film or a cluster of droplets forms due to factors like surface tension and gravity,resulting in complex morphologies that are not accurately represented by simplified shapes such as circular arcs.The presence of these films significantly influences infrared target detection,optical windows,stealth coatings,solar photovoltaic panels,and porous structures used in solar interface evaporation by altering spectral radiation transmission and properties,thus affecting infrared signal transmission and energy conversion processes.Current studies focus primarily on the effects of liquid droplets,with analyses often limited to factors like droplet size,distribution,and surface properties.These studies typically employ large-scale parameters and geometric optics approximations.However,for thin liquid films at micro-and nanoscale thicknesses,there is limited in-depth research on their spectral radiation transmission and properties.In this paper,we aim to establish accurate models of surfaces covered with liquid films and investigate the spectral reflection characteristics of such surfaces at micro-and nanoscale levels.Methods We employ a theoretical liquid film profile derived from the Young-Laplace equation to construct microgroove structures with liquid films of varying thicknesses.The finite-difference time-domain(FDTD)method is used to simulate radiation transmission and assess the effects of liquid film thickness,groove width,angle of incidence,and wetting angle on the spectral reflection properties.The analysis covers the reflectance and electric field distribution across different wavelengths,providing insights into the spectral reflection patterns of surfaces with liquid films.Results and Discussions Simulations indicate that theoretical profiles of liquid films differ significantly from circular approximations,with r

关 键 词：表面光学 含液膜微槽 光谱反射特性 杨-拉普拉斯方程 时域有限差分法 

分 类 号：O436[机械工程—光学工程] TK121[理学—光学]