Dual boundary element analysis for fatigue behavior of missile structures

Abstract

The fatigue behavior of a crack in a missile structure is studied using the dual boundary integral equations developed by Hong and Chen (1988). This method, which incorporates two independent boundary integral equations, uses the displacement equation to model one of the crack boundaries and the traction equation to the other. A single domain approach can be performed efficiently. The stress intensity factors are calculated and the paths of crack growth are predicted. In order to evaluate the results of dual BEM, four examples with FEM results are provided. Two practical examples, cracks in a V‐band and a solid propellant motor are studied and are compared with experimental data. Good agreement is found.本文使用洪及陳(1988)所發展的對偶邊界元素法分析飛彈結構的疲勞行為。此方法結合二個獨立的邊界積分方程式，兩式可同時考慮裂縫邊界的兩側，有效地使用單一領域即可處理裂縫問題。包括應力強度因子的計算結果以及裂縫成長路徑之預測，將與影線元素法做比較。其中有二個實際應用例分別為含裂縫之V型環以及固體火箭發動機，經與實驗結果做比較，可得到一致的結果。