Application of the Boundary Element Method to Fatigue Crack Growth Analysis

摘要

This investigation analyzes a crack emanating from one hole, and approaching a second hole, in a two hole tension strip with finite boundaries using the Boundary Element Method. The study included the effects of varying the hole diameter, hole separation and the length of the geometric correction factor Beta, which can be presented as a family of curves. An example damage tolerance analysis is presented with the Beta curves being incorporated into a Beta look-up table as used in the NASA/FLAGRO fatigue crack growth program. This technique is acceptable in most fatigue crack growth programs now used in the aircraft industry to ensure aircraft structural integrity. Several classic fracture mechanics problems are analyzed, and computational efficiency as compared to conventional finite element techniques is investigated. Agreement with analytic solutions as well as other numerical methods (finite element) is excellent. The computation efficiency was shown to an improvement over existing methods. Keywords: Cracking(Fracturing); Theses. (SDW/JES)