多孔材料辐射特性的实验研究

发布时间：2018-05-20 08:50

本文选题：多孔材料 + 空腔效应　；参考：《中国矿业大学》2015年硕士论文

【摘要】：目前多孔材料在辐射方面的研究还不够深入,为了明确辐射在多孔材料表面的传热特性,得到不同孔参数的多孔材料辐射能力的评价方法,指导工业生产中多孔材料的设计,本文对多孔材料的辐射特性进行研究,通过明晰多孔材料不同参数对其辐射的影响规律,揭示多孔材料腔体的“空腔效应”,进一步完善辐射理论,对“空腔效应”提供借鉴。本文搭建了多孔材料辐射实验装置,研究了单孔材料,简单多孔材料以及复杂多孔材料“空腔效应”的影响规律。实验结果表明,表面发射率的变化基本不受材料温度、开孔形状、开孔分布的形状、孔深度分布情况这4个参数的影响;表面发射率随着孔径的增大呈现先增长后下降的趋势;材料表面发射率随着孔深度的增加,呈现先增长再平稳的趋势;随着深径比的增大,表面发射率增大;随着孔朝向与表面法线夹角的余弦值的减小,表面发射率的平均值逐渐降低;材料表面发射率随着孔第二层深度的增加,呈现先增长再平稳的趋势;材料表面发射率随着孔第二层孔直径的增加,整体发射率增长呈现先缓慢增长再急速增长的趋势。根据实验数据对单孔材料、简单多孔材料进行了公式拟合,并将多孔材料的实验结果与计算值比较,验证了公式的适用性。
[Abstract]:At present, the research on radiation of porous materials is not deep enough. In order to clarify the heat transfer characteristics of radiation on the surface of porous materials, the evaluation method of radiation capacity of porous materials with different pore parameters is obtained to guide the design of porous materials in industrial production. In this paper, the radiation characteristics of porous materials are studied. By clarifying the influence of different parameters of porous materials on their radiation, the "cavity effect" of porous material cavity is revealed, and the radiation theory is further improved, which can be used as a reference for "cavity effect". In this paper, an experimental apparatus for radiation of porous materials is set up, and the influence of single porous materials, simple porous materials and complex porous materials on the "cavity effect" is studied. The experimental results show that the change of surface emissivity is not affected by the four parameters of material temperature, hole shape, hole distribution and hole depth distribution, and the surface emissivity increases first and then decreases with the increase of pore size. With the increase of hole depth, the surface emissivity of the material increases first and then steadily; with the increase of aspect ratio, the surface emissivity increases; with the decrease of cosine value of the angle between the hole orientation and the surface normal line, the surface emissivity increases with the increase of the ratio of depth to diameter. The average emissivity of the surface decreases gradually, the emissivity of the material increases first and then steadily with the increase of the depth of the second layer of the hole, and the emissivity of the material increases with the diameter of the second layer of the hole. Overall emissivity growth shows the trend of slow growth first and then rapid growth. According to the experimental data, the formula fitting of single porous material and simple porous material is carried out, and the applicability of the formula is verified by comparing the experimental results of the porous material with the calculated values.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.4

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