ID | 11206 |
Eprint ID | 11206
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FullText URL | |
Title Alternative | Numerical Analysis Model of Forced Convection Heat Transfer of a Layer of Spherical Particles Considering Boundary Wall Effect
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Author |
Ozaki, Koichi
Inaba, Hideo
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Abstract | A simple model for the heat transfer and pressure drop characteristics in a layer of spherical particles is proposed in the present study. The layer of spherical particles bounded by two parallel boundary walls is considered to consist in two regions, one of which is the near-wall region of particles within a half-diameter of the spherical particle from the wall, and the other is the core region of particles over a half-diameter of the spherical particle away from the wall. The characteristics of the near-wall region, such as the permeability, the Forchheimer coefficient, and the thermal dispersion coefficient, are determined based on the experimental data for a one-stage spherical particle layer. For the core region, the permeability and the Forchheimer coefficient are evaluated using previous correlations for a homogeneous spherical particle layer, while the thermal dispersion coefficient is modified from that given by the previous correlation for a homogeneous spherical particle layer to include the effect of the thermal conductivity ratio of the spherical particle and the fluid. The effective thermal conductivity of the layer of spherical particles is assumed to be constant in the present model. The validity of the model is proved by comparing the results of this analysis with experimental results under various conditions.
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Abstract Alternative | 本報では、比較的大きな直径(d=9.54~21.2mm)を有する球状粒子一段充填層に関する実験結果に基づく、壁近傍領域の流動・伝熱モデルの提案を試みる。具体的には、粒子充填層としての物理的意味が損なわれないよう、粒子直径程度のスケールを用いてミクロな立場の基礎式を空間平均化する。得られた粒子充填層に関する基礎式中の有効熱伝導率、浸透性、Forchheimer係数等の諸特性値は次のように評価する。前報の結果に基づき、球状粒子充填層が、壁面より粒子直径の半分までの壁近傍領域と、壁面より粒子直径の半分以上離れたコア領域の二領域から構成されると考え、各領域における諸特性値は、微細なスケールでの変化を考慮せず、その平均値にて一定とみなした扱いを行う。また、実験条件の大きく異なる従来の実験データとの比較も行い、本解析法の有用性についても検討を行う。
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Keywords | Spherical Particle Layer
Forced Convection Heat Transfer
Effective Thermal Conductivity
Numeical Analysis
Wall Effect
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Note | 本文データは学協会の許諾に基づきCiNiiから複製したものである
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Published Date | 1996-11-25
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Publication Title |
日本機械学會論文集 B編
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Publication Title Alternative | Transactions of the Japan Society of Mechanical Engineers B
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Volume | volume62
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Issue | issue603
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Publisher | 社団法人日本機械学会
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Publisher Alternative | The Japan Society of Mechanical Engineers
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Start Page | 172
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End Page | 179
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ISSN | 0387-5016
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NCID | AN00187441
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Content Type |
Journal Article
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Official Url | http://ci.nii.ac.jp/naid/110002395119/
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language |
Japanese
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Copyright Holders | 社団法人日本機械学会
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File Version | publisher
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Refereed |
True
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