本研究主要目的在於利用數值模型模擬方式討論平板式磁致冷裝置AMR(active magnetic regenerator)在各種參數下其性能表現。使用套裝軟體COMSOL來模擬計算AMR統御方程式，方程式由流體部分能量方程式和固體部分能量方程式構成，為一組一維暫態偏微分方程式。除了分析AMR內部的熱傳現象，最主要的目標是找出在限制條件下，如何改變操作參數以提升冷凍能力，以及參數變化和AMR性能表現的關係。

摘要 I
致謝 II
第一章 緒論 1
1-1 前言 1
1-2 磁製冷簡介 3
第二章 理論與文獻回顧 5
2-1 磁熱效應 5
2-1.1 熱力學理論 5
2-1.2 一階相變與二階相變 9
2-2 磁熱材料 10
2-3磁場 16
2-4 磁致冷復熱器（active magnetic regenerator, AMR） 18
2-4.1 AMR循環 19
2-5 AMR能量守恆方程式 21
2-5.1流體部份能量守恆 22
2-5.2材料部份能量守恆 24
2-6文獻回顧 26
2-6.1磁致冷裝置 26
2-6.2 磁致冷裝置（AMR）數值模型 39
第三章 數值模型模擬 43
3-1 模擬軟體介紹 44
3-1.1 COMSOL Multiphysics簡介 44
3-2平均場理論模型（mean field model）與計算 45
3-2.1平均場理論模型（mean field model） 45
3-2.2 求解Gd熱力學性質 47
3-3 模型幾何參數設定 49
3-4 一維AMR統御方程式 50
3-4.1質量流率與磁場控制 52
3-4.2邊界條件 53
3-4.3初始條件 53
3-4.4方程式參數設定 54
3-5 性能評估參數 56
第四章 模擬結果與討論 57
4-1基本結果 58
4-2週期的影響 63
4-3片數的影響 66
4-3.1改變片數對不同溫度差的影響 66
4-3.2改變片數對不同週期的影響 72
4-3.3改變片數對不同U的影響 74
4-4軸向熱傳導的影響 76
第五章 結論 80
參考文獻 81

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