Fatigue life analysis of T-38 aileron lever using a continuum damage approach

摘要: In a recent investigation conducted by the United States Air Force, mechanical failure of aileron lever, manufactured from 2014-T6 aluminum, caused fatal mishap T-38 trainer aircraft. general locations cracks are unknown and must be determined simulation. this study we propose to use continuum damage modeling approach determine degradation in material as number cycles loading increases. This successfully predicts location crack initiation, propagation path, rate. A stress-based model conjunction with successive initiation technique is utilized. Successive based on idea that will accrue material. Each element inside new have value 0 assigned it. Over time, occurs due stresses individual elements add until reaches 1. At point, occur. code was developed ANSYS can draw, mesh, apply appropriate forces lever for runs. By using S-N curve aluminum material, constants found. then used state each element. time stressed, particular amount When an specific damage, "kill" element, resulting no longer adding stiffness matrix Variability common occurrence all aspects engineering such manufacturing, testing, loading. Monte Carlo simulation sensitivity results variability input parameters ± 15%. Input include loads, properties constants. The indicates only significant life exponential fatigue equation. Material load variations range not significantly change prediction results.