Experimental Study of Fluid Flow and Heat Transfer Characteristics in the Square Channel with a Perforation Baffle
鄭森耀、黃國修
E-mail: [email protected]
ABSTRACT
This work performed a detailed measurement of heat transfer coefficients in a square channel with a step baffle and perforation baffle by using the transient liquid crystal method. The varied parameters were Reynolds number and the baffle height、different hole number. The results showed that the enhancements of local heat transfer appeared in the leading edge of the baffle due to the impinging effect. Proved that some high temperature often burns out the part, instead of be burnt out by the whole too high horizontal temperature by the experiment. Obstacle piece cliff side hot to strike effect is most easy to be it accumulates hotly to produce. Proposing boring a hole, the figure scatters evenly in a cliff side of obstacle, lengthen the life-span of the component. When gas crosses the more porous obstacle one, after the gas flows through many holes in a utensil to keep in touch again, will produce more turbulence it causes system to be hot to be relatively average to spread coefficient, favorable as to whole system.
Keywords : Transient liquid crystal method, perforation baffle, channel flow, step baffle, Reynolds number Table of Contents
封面內頁 簽名頁 授權書---iii 中文摘要---v 英文摘 要---vi 誌謝---vii 目
錄---viii 圖目錄---x 表目
錄---xii 符號說明---xiv 第一章 研究背景與目 的---1 1.1 背景與目的---1 1.2 研究目
標---2 第二章 理論分析---3 2.1 液晶的特
性---3 2.2 文獻回顧---4 2.2.1液晶在熱傳研究之應 用---5 2.2.2背向階梯熱傳之研究---7 第三章 研究設備與進行步 驟---11 3.1 實驗理論---11 3.2 實驗設
備---12 3.2.1 影像擷取設備---12 3.2.2 數據擷取設 備---13 3.2.3 實驗測試段---13 3.2.4 加熱設
備---15 3.2.5 液晶---15 3.2.6 影像分析程
序---17 3.3 實驗程序---17 3.4 實驗參數之不準確度分 析---19 第四章 實驗結果與討論---22 4.1 空槽熱傳效
應---22 4.2 不等高障礙塊熱傳效應---23 4.2.1不等高度未穿孔障礙塊熱傳效 應---23 4.2.2不等高度不同孔數障礙塊熱傳效應---24 4.3 不等高度障礙塊紐塞數分布效
應---25 4.4 不等高度相同Re數障礙塊熱傳效應---26 4.5 不等高度不同孔數障礙塊紐塞數分布 效應---28 4.6 Re與h/H對Nu分布影響---29 第五章 結論與建
議---31 5.1 研究結論---31 5.2 建 議---33 參考文獻---71 REFERENCES
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