遙場渦電流檢測是一種渦電流非破壞檢測方法，這種方法已經被廣泛使用在檢驗碳鋼管束，如熱交換器或是鍋爐上之管束。遙場渦電流檢測主要是利用激發線圈所產生之低頻電磁場與接收線圈上之相位角差值來判斷缺陷。然而在不同管壁材質之電磁性質與不同缺陷型態影響下，往往導致不同之檢測結果。
本文目的在於使用有限元素法，分析各種影響因子對於遙場渦電流檢測所造成之影響。在軟體部分，利用Femlab軟體建立電磁模組，在經過數值分析後，由Matlab軟體進行後處理，繪製電壓平面圖與深度評估曲線。將模擬結果與實際案例比對後證實為可行的，並針對不同之影響因素，分析遙場渦電流訊號圖變化情形。
經由本研究，已成功的建立一套遙場渦電流有限元素分析的模型，經由有限元素模擬分析出來之結果，可以提供實際檢測更多之比對數據，使實際檢測能夠更正確的判定缺陷之狀況，進而降低評估誤差的產生，增加檢測之準確度、可靠度。

Remote field eddy current (RFEC) testing is an eddy current non-destructive test method that has become widely used for the examination of carbon steel tubes, such as those found in heat exchangers and boilers. RFEC testing relies on the use of very low intensity electromagnetic fields on the exciting probe. The defect detection is carried out considering the phase difference between the exciting and pickup signals. However, various testing effects were produced because the affection of different electromagnetic characteristics of tubes and types of defects
The purpose of this study is to analyze the influential factors of RFEC testing accuracy by means of the finite element method (FEM). In order to investigate the numerical simulation, the researcher used the finite element software package FEMLAB to create an electromagnetic model of RFEC testing. Then he applied the mathematics software package MATLAB to plot the voltage plane diagram and defect-phase difference diagram. After the comparison of the simulation with experiments, the researcher confirmed the reliability of electromagnetic simulation. As a result, this study provides the variations in RFEC testing result diagrams for the influential factors.
Over all, this study has successfully established an FEM RFEC electromagnetic model. After the FEM simulation, this method can provide many comparable data for experimenter. This study may remedy the different types of defects and reduce assessing error. Therefore, the accuracy and reliability of testing of RFEC can be accessed.

目錄 i
表目錄 iv
圖目錄 v
中文摘要 ix
英文摘要 x
第一章 緒論 1
1.1前言 1
1.2文獻回顧 2
1.3研究動機與目的 4
1.4研究目的 5
第二章理論分析 7
2.1研究流程 7
2.2遙場渦電流檢測簡介 7
2.3電磁理論基礎方程式 8
2.4有限元素模擬之理論基礎方程式 10
2.5集膚—深度理論 15
2.6渦電流之主要影響因素 16
第三章 遙場渦電流之有限元素模擬 19
3.1 有限元素法模型建立 19
3.2 各項模型之參數設定 20
3.3 有限元素分析 22
第四章FEM模擬分析結果討論 23
4.1FEM模擬與實驗案例比較 23
4.2管壁厚度對遙場渦電流檢測之影響 23
4.3支撐板變化對遙場渦電流檢測之影響 24
4.3.1 支撐板厚度 24
4.3.2 支撐板孔徑與間隙 25
4.4缺陷型態對遙場渦電流檢測之影響 26
4.5管束材質對遙場渦電流檢測之影響 26
4.5.1 管壁導磁率影響 26
4.5.2 管壁導電率影響 27
4.6其他因素 28
4.6.1 頻率影響 28
4.6.2 內外缺陷 28
4.6.3 缺陷厚度 28
第五章 結論 30
參考文獻 78

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