泡沫炭传热建模仿真研究进展

Research progress on heat transfer modeling simulation of mesophase-pitch-derived carbon foam

泡沫炭因其结构性能好、可调节性强等优点,被视为优异的热管理材料,拥有广阔的应用前景,基于其多孔特性,探究其导热性能和结构的关系成为研究热点。传热仿真研究可以指导泡沫炭孔道结构和制备方法的进一步改良与设计。本文总结了泡沫炭传热仿真研究的几何结构基础和各向异性特征,介绍了几种现有的泡沫炭传热仿真理想化模型和各向异性模型,阐述了泡沫炭传热有限元研究的基础理论和仿真方法,整理了对几何模型和传热仿真结构进行有效性验证的方法,最后对泡沫炭传热建模仿真的发展方向进行了展望。作者认为,泡沫炭传热仿真研究需要以其多孔几何结构及几何参数为基础,研究的重难点为由泡孔结构和石墨本身性质决定的各向异性,现有的理想几何模型主要包括面心立方模型、体心立方模型、正四面体模型、正八面体模型、随机分布模型、随机算法模型,各向异性模型主要有椭球形体心立方模型、发泡机理模型、开尔文十四面体模型和三维计算机断层扫描模型4种,对泡沫炭的传热研究均具有重要参考价值。泡沫炭传热有限元研究一般使用ANSYS或ABAQUS软件计算其固体骨架热传导性,使用实验测量数据或Klett理论模型可以对模型有效性进行验证。鉴于泡沫炭石墨片层结构无法通过宏观几何建模实现,需要探究更加准确的各向异性多孔材料传热模拟方法,研究泡沫炭石墨韧带及片层排布的有序性与其制备条件及有效热导率的关系,便于进一步研究泡沫炭各向异性传热机理。

Carbon foam is regarded as an excellent thermal management material because of its good structural properties and strong ad-justability,and has broad application prospects.Based on the nature of its porous material,the relationship between thermal conductivity and structure has become a research focus.Heat transfer modeling and simulation can guide the further improvement and design of carbon foam pore structure and preparation method.This paper summarizes the geometric structure basis and anisotropy characteristics of carbon foam heat transfer simulation research,introduces several existing carbon foam heat transfer simulation idealized models and anisotropy models,expounds the basic theory and simulation methods of carbon foam heat transfer finite element research,and sorts out the methods to verify the effectiveness of the geometric model and heat transfer simulation structure.Finally,the development direction of carbon foam heat transfer modeling and simulation is prospected.The authors believe that the heat transfer simulation of carbon foam should be based on its porous geometric structure and geometric parameters,and the main difficulties are the anisotropy determined by the pores structure and the properties of graphite itself.The existing ideal geometric models mainly include face-centered cubic model,body-centered cubic model,tetrahedral model,octahedral model,random distribution model,random algorithm model,and regular tetrahedral model.Anisotropic models mainly include ellipsoidal body-centered cubic model,foaming mechanism model,Kelvin tetrahedron model and three-dimensional computed tomography model,all of which have important reference value for the heat transfer research of carbon foam.The fi-nite element research of carbon foam heat transfer generally uses ANSYS or ABAQUS software to calculate the thermal conductivity of its solid skeleton.The validity of the model can be verified by using experimental measurement data or Klett theory model.Since the carbon foam graphite lamellar structure cannot be realized by macroscopic geometric modeling,it is necessary to develop more accurate heat transfer simulation methods for anisotropic porous materials,and study the relationship between the order of the carbon foam graphite liga-ment and lamellar arrangement,its preparation conditions and effective thermal conductivity,for further studying the anisotropic heat transfer mechanism of carbon foam.