光纖光源、雷射、放大器等，摻鉻晶纖的角色都為增益介質，從輸入幫浦光源到最後的輸出能量的整個過程，要經過能量轉換，只要是能量轉換，其轉換效率絕非百分之百，所以每個過程都有能量損失，絕大部分的損失能量都變成熱能。本文主要是透過理論分析的模式，研究在雷射光源幫浦激發連續波操作下，摻鉻釔鋁石榴石晶纖其內部能量轉換所產生的熱效應。並藉由通用有限元素分析軟體ANSYS之便，評估於不同幫浦瓦數激發下摻鉻晶纖於穩態時的最高溫度、溫度分佈、熱應力狀態。幫浦光源於晶纖內會隨著傳播方向，呈現exp(-αz)的衰減，所以當光源射入時，在越接近光源入射的端面的區域會有較多的熱源產生，在3 W單端面幫浦激發下晶纖最高溫度達到397K出現在光源入射端面附近，同時最大拉伸應力為39 MPa在YAG與silica交界處。稍後更計算不同的狀況下的溫度分布與熱應力。

In this thesis, thermal effects on Cr4+:YAG fiber are studied through numerical modeling. Crystal fiber was used as the gain medium in amplified spontaneous emission(ASE) light source, lasers, or amplifiers. Because the absorbed pump power can not be completely turned to signal in energy transition, some of the absorbed pumping power will be converted into heat, which raises the fiber temperature. In continuous-wave regime, maximum temperature, the steady-state temperature profile, and thermal stresses in the host material under single end pump are obtained by using the commercial finite elements method software ANSYS. The pump power was propagated with exponential decay inside the fiber. Because more heat was generated at the light incident region, a maximum temperature of 397K was observed from the simulation result at the same region under single-end pump of 3W. Simultaneously, a maximum tensile stress of 39 MPa was reached at the border between YAG and Silica. Finally, temperature profiles and thermal stresses were calculated in the other conditions.

中文摘要 I
Abstract II
表目錄 V
圖目錄 VI
第一章 緒論 1
1-1 前言 1
1-2 文獻回顧 2
1-3 研究動機及目的 4
第二章 理論與數值模擬 5
2-1 線性與非線性分析理論 5
2-1-1 線性分析理論 5
2-1-2 非線性分析理論 7
2-2 熱源評估 9
2-3 ANSYS有限元素分析軟體 12
2-3-1 有限元素法分析 12
2-3-2 耦合場分析定義 13
2-3-3 基本假設 15
2-3-4 ANSYS分析步驟 15
第三章 模擬結果與討論 20
3-1 相近的實例模擬 20
3-2 模擬自然對流冷卻的裸晶纖 21
3-2-1 材料性質為常數時 22
3-2-2 材料性質為溫度的函數時 25
3-2-3 披覆層的大小對溫度與熱應力的影響 27
3-3 模擬導熱金屬包覆的晶纖且連接TE cooler等散熱元件 29
3-3-1 溫度分布與熱應力 29
3-3-2 披覆層的大小對溫度的影響 30
第四章 結論 32
參考文獻 34

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