Mesoscopic lattice Boltzmann model for radiative heat transfer in graded-index media

• Published in: Physical review research Vol. 4; no. 1; p. 013125
• Main Authors: Liu, Xiaochuan, Wu, Si, Zhu, Keyong, Cai, Yuepei, Huang, Yong
• Format: Journal Article
• Language: English
• Published: American Physical Society 01.02.2022
• ISSN: 2643-1564; 2643-1564
• DOI: 10.1103/PhysRevResearch.4.013125

Convection, conduction, and thermal radiation are the three mechanisms of heat transfer in nature. The lattice Boltzmann model (LBM) has already achieved great success in dealing with convection and conduction problems. However, the mature LBM for radiative heat transfer (RHT) is still relatively lacking. Here we propose a mesoscopic LBM for RHT in graded-index media, which enables a simple and efficient solution of both transient and steady-state RHT in graded-index media by conducting collision and streaming processes. Via the Chapman-Enskog analysis, the radiative transfer equation of graded-index media is rigorously derived from the proposed LBM. The present LBM is a universal model for RHT in media with arbitrary refractive index distribution, which can naturally handle RHT in homogeneous media with constant refractive index. This model is expected to provide a simple and efficient mesoscopic tool for RHT in complex media and pave the way for establishing a unified framework of LBM for convection, conduction, and thermal radiation heat transfer.