具正多邊形頂立體楔形熱阻(RPSWT)模型之絕熱正多面體的熱傳特性

The Heat Transfer Characteristics of an Insulated Regular Polyhedron by Using a Regular Polygon-top Solid Wedge Thermal-resistance (RPSWT) Model

李永祥(Yung-hsiang Lee)

指導教授 ： 周煥銘 ； 黃景良

崑山科技大學/工程學院/機械工程研究所/碩士(2003年)

https://doi.org/10.6828/KSU.2003.00009

摘要

本文使用一由立體角(solid angle)的觀念下導出的具正多邊形頂立體楔形熱阻(RPSWT)模型，對絕熱正多面體的臨界厚度與中性厚度及熱傳導特性之研究。本文發現，絕熱正多面體與絕熱球體有相同的無因次熱傳特性，即使它們的實際熱傳率並不相同。本文同時也發現習用之固定表面積之平板模型不能被用來分析絕熱正多面體，尤其是在微小至中間形體尺寸和/或較大絕熱厚度時。具正多邊形頂立體楔形熱阻(RPSWT)模型亦可被應用於使用複合材料之正多面體和正多邊形頂立體楔形塊的熱傳導問題上。

關鍵字

熱傳特性 ； 楔形熱阻 ； 立體角

並列摘要

The relation of the critical and the neutral thickness and heat transfer characteristics for an insulated regular polyhedron are investigated by using a new regular polygon-top solid wedge thermal-resistance (RPSWT) model obtained from a solid angle concept. It is found that the dimensionless heat transfer characteristics of the insulated polyhedrons are the same as those of an outside tangent insulated sphere even though their actual heat transfer rates are different. It is also found that the conventional constant surface area plate model cannot be used to analyze the insulated polyhedrons, especially in situations of small to medium body-size and/or with a greater insulation thickness. The single RPSWT should also be applied to the heat transfer problems of the regular polygon-top wedge block and regular polyhedron with complex material layers and more reasonable results can be obtained.

並列關鍵字

solid wedge thermal-resistance ； heat transfer characteristics ； solid angle

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