微结构表面热辐射光谱特性研究分析的一个主要问题在于表面微结构复杂的空间自由度以及计算方法。针对以上问题本文建立了任意微结构表面的物理模型,基于电磁波理论给出了微结构表面热辐射满足的麦克斯韦方程组。将时域有限差分方法(FDTD)用于麦克斯韦方程组的离散求解,引入场分离处理方法,直接计算提取反射场量,进而采用坡印廷定理计算得到能流以及光谱特性。最后,分别计算了随机微结构表面和微腔表面的热辐射光谱特性,并与相关文献的实验以及计算结果进行了比较。
Simulation of thermal spectral properties of microstructured surface meets great challenge due to its complicated degrees of freedom in a system profile. This paper presents a theoretical model of microstructured surface, and the corresponding Maxwell equations is given based on electromagnetic wave theory for investigating the spectrally radiative properties. The finite difference time domain (FDTD) algorithm is developed to solving the Maxwell equations, and the reflection fields are obtained by the field split technique, then the energy flux flow and thermal spectral properties are calculated by using Poynting law from the reflection components. Finally, the spectral properties of random roughness surface and microcavity surface are simulated with the developed FDTD algorithm, and the results are compared with the experimental data and simulated results elsewhere.