臺灣博碩士論文加值系統

摘要
本文主要研究長方形容器內置鯖魚置放於冷凍室之凍結速率。主要參數包括冷凍物品與地面之間距實驗量測，以及在容器內部鯖魚間埋入熱傳導性良好之鋁條，來提升冷凍物品之結凍效率。在數值求解方面，使用套裝軟體「I-DEAS」來模擬冷凍室之三維速度與溫度場的分佈情形。
由結果顯示與實驗量測值相符，驗證其正確性。其次在冷凍物品中央部份埋入鋁條，不管縱向或橫向，垂直或水平面均明顯提升，使得冷凍物品中央局部高溫區域熱量得以藉鋁條散出，達到均勻降溫之效果;在埋入兩支鋁條之案例中，不論是縱向或橫向，均以垂直擺置較佳，其兩者又以縱向較好;其次埋入四支鋁條之案例中，分別以水平、垂直各兩支擺置，發現以縱向的擺置較佳。

ABSTRACT
In this paper, the frozen rate of a rectangle container full of mackerel fish in a freezer is studied. The gap between the container and ground of freezer was varied to measure the flow and thermal fields. In addition, aluminum bars are placed into the middle portion of the container to increase the frozen rate. Both experimental and theoretical works have been conducted. A software I-DEAS is applied to simulate the air circulation in the freezer.
It is found that the calculations agree well with the data from experiments in the cases by varying thickness of the gap, which results in increasing the frozen rate. As for embedded aluminum bars inside the contained which is favorable in frozen effect in all the directions of allocation. The local hot region is effectively reduced through the highly conductive metal added. It is concluded that the performance of enhancement is more pronounced, when the axial direction of bars is in the longitudinal direction.

目錄
中文摘要..................................................i
英文摘要..................................................ii
目錄.....................................................iii
符號說明..................................................vi第一章 緒 論...............................................1
1-1 前言...............................................1
1-2 文獻回顧...........................................2
1-3 研究目的...........................................7
第二章 實驗量測............................................8
2-1 實驗設備...........................................8
2-2 實驗規劃..........................................10
2-3 實驗步驟..........................................10
第三章 理論分析...........................................12
3-1 數值方法簡介......................................12
3-2 物理模型..........................................12
3-3 基本假設..........................................14
3-4 統御方程式........................................15
3-5 紊流模式..........................................16
3-6 數值求解程序......................................17
3-6-1 基本元素有限體積法簡介........................17
3-6-2 離散方程式....................................18
3-7 數值模擬程序......................................21
3-8 熱傳分析..........................................23
3-8-1 紐塞數 .......................................24
3-8-2 熱傳量 .......................................25
第四章 結果與討論.........................................33
4-1 實驗量測結果......................................33
4-1-1 不同離地高度之分析 ...........................33
4-1-2 冷凍物品不同量測點之分析 .....................34
4-2 數值模擬結果 ............................. .......35
4-2-1冷凍物品及周圍之熱流場分析....................36
4-2-2加裝鋁條之冷凍物品及周圍之熱場分析............37
4-3 不同離地高度之模擬比較............................38
4-4 實驗量測和模擬之比較..............................39
4-4-1冷凍物品對冷凍室不同離地高度之比較............39
4-4-2相同離地高度下實驗量測和模擬實際狀況與擺置
鋁條之冷凍物品之比較 .........................41
4-5模擬一小時對埋入鋁條時間之冷凍物品之比較 .......42
第五章 結論...............................................76
參考文獻…………………………………………………………………78

參考文獻
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