本文是使用有限元素分析軟體ANSYS來分析橢圓形凹槽圓管，在循環彎曲負載下所呈現的力學行為 (彎矩 (M)-曲度 (κ) 及橢圓化 (ΔD/D)-曲度 (κ)關係)。本文分析流程是先以彎管實驗機及曲度-橢圓化量測器，進行無凹槽316L不銹鋼圓管的力學行為的實驗後，將該實驗結果以有限元素ANSYS進行分析，並求得所對應的相關材料參數；隨後建立橢圓形凹槽圓管的ANSYS分
析模式，並將求得的材料常數代入有限元素ANSYS的運算架構中，來分析橢圓形凹槽圓管在循環彎曲負載下的力學行為。而圓管的橢圓形凹槽將分析兩種情況，分別為固定凹槽的深度 (橢圓形短軸的長度)，但變動凹槽的寬度 (橢圓形長軸的長度)；另一種為固定凹槽的寬度，但變動凹槽的深度。分析的結果顯示，具凹槽的圓管在承受循環純彎曲負載時，圓管橢圓化的大小呈現不對稱的累積成長現象。

The purpose of this paper is to use the finite element software, ANSYS,
to analyze the mechanical behavior (the relationship of moment - curvature
and ovalization - curvature) of elliptical-notched circular tubes subjected to cyclic bending. The analysis process is to first test unnotched 316L stainless steel tube using a tube-bending machine and curvature-ovalization measurement apparatus. Then, using the finite element ANSYS system to analyze the mechanical behavior, the relative material parameters for this material can also be determined. Next, the finite element ANSYS model for elliptical-notched circular tube is built, and the determined material parameters are used in the calculation structure to find the mechanical behavior of elliptical-notched circular tubes under cyclic bending. Two situations of elliptical notch are considered in this study, one is a notch with a fixed depth (length of the short axis of the ellipse) but variable notchwidths (length of the long axis of the ellipse), and the other is a notch with a fixed width but with variable depths. Based on the analysis result,important behavioral trends are deduced.