燃料電池效能決定於兩大部分，電化學反應式的活性以及電池元件的工作性能。本論文研究主要目的為分析流道板界面於實際運作時介面封裝及結構可靠度評估，並建立數值模擬等分析模式。流道板上存在一表面裂縫並且受到流場中流體的剪應力及壓應力的影響，將會導致裂縫產生並且成長，使得表面產生剝落現象。由結果可得入口壓力會較入口速度影響SIF更甚。而且當裂縫長度增加時，KI會隨之增加但KII卻是輕微減少。在微流道壁上所存在於Ag-SU8之層間裂縫可靠度分析也將會在本文中做探討。

The efficiency of the fuel cell depends on both the kinetics of the electrochemical process and performance of the components. The main aim of this research is to analysis the reliability of the cracked Ag-SU8 interface on the channel wall in a micro-PEMFC. An existed surface crack on the channel wall subjected to the flow induced compressive stresses and shear stresses will propagate and lead to the spall formation. The results show that as the crack length increases, the value of KI will increase, but the value of KII decreases slightly. The reliability analysis of the interfacial crack between Ag and SU8 on the Micro-channel wall in PEMFC is discussed in this thesis.

Contents …………………………………………………………………....I
List of Figures ……………………………………………………………III
List of Tables ………………………………………………………….....VI
Abstract (In English) …………………………………………………...VIII
Abstract (In Chinese) .…………………………………………….……...IX



Chapter 1 Introduction ………………………………………………….. 1
1.1 Background of Fuel Cell ...........……….……………………..…….1
1.2 Basic Principle of Fuel Cell …..……………………………………2
1.3 Research Objective ………………………………….……………3
1.4 Literature Review …………………………………….....………....4
1.4.1 Several Kinds of Analysis in Fuel Cell ……………...…..…..4
1.4.2 Flow Field in the Micro-Channel ………………...……….....5
1.4.3 The Interface Simulations in FEM ……………..………….6
1.4.4 Different Crack Types in the Material …………………….8
1.4.5 Different Crack Simulations in the Bimaterial ..……………10
Chapter 2 Numerical Simulation ………………………………………...15
2.1 Analyzing Stress State of the Micro-Channel Wall ……………15
2.1.1 Three-Dimension Model of the Micro-Channel ……………15
2.1.2 Boundary Condition ………………………………………16
2.1.3 Introduction of the FLOTRAN CFD Analysis and Elements .17
2.1.4 Determination of Slip Boundary ………….…………….......20
2.2 Crack Analysis Using Finite Element in Bimaterial …………….23
2.2.1 Finite Element Method …………………...…………….…23
2.2.2 Theory of Crack Analysis in Bimaterial ………….…………24
2.2.3 Accuracy of Mesh …………………………………………26
2.2.4 The Quarter-Point Element ………………………………..28
2.2.5 The Model Used …...………..………………………..……..30
2.2.6 Mesh Sensitivity and Convergence near the Crack Tip…….31
2.2.7 Analysis Procedure ………………………………………..32
2.3 Taguchi-Method and Analysis-of-Variance ………………………33
2.3.1 Taguchi-Method …………………………………………...33
2.3.2 Analysis-of-Variance ……………………………………...35
Chapter 3 Relations between SIF and Properties Proportion of bimaterial.53
Chapter 4 Results and Discussions ...……………………….………....…58
4.1 Different Effects of Parameters in Flow Field Analysis ……….…58
4.1.1 Effects of Different Channel Lengths ……………………….58
4.1.2 Effects of Different Crooked Radii …………………………59
4.1.3 Effects of Different Gas Inlet Velocities …………………..59
4.1.4 Effects of Different Gas Inlet Pressures …………..………60
4.1.5 Effects of Different Widths between Two Legs …………….60
4.1.6 Effects of Different Channel Widths ………………………..61
4.1.7 Analysis of Slip Boundary …………………………………..61
4.2 Simulations of Edge-Crack in Bimaterial Interface ……………...63
4.2.1 Different Effects of Parameters on SIF ……………………..63
4.3 Results of Taguchi Method and Analysis of Variance ……………64
Chapter 5 Conclusions ……………...….………………………….….….86
References …………………………………………………..……………88

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