Fatigue Life Estimation of Fuselage Structure Due to Fluctuating Bending Loads

Aircraft structure is the most obvious example where structural efficiency results in light weight and high operating stresses. Airframe experiences variable loading in service. It is quite unlikely that the structure will fail due to a static overload. Aerodynamic load distribution on the airframe will make the fuselage structure to bend about wing axis. Bending of the fuselage structure introduces both tension and compression stress field in the structure. Linear static stress analysis is carried out for identification of the fatigue critical locations. The project includes the fatigue life estimation for the fuselage structure due to fluctuating loads on the fuselage. Stress analysis of the segment of the fuselage will be carried out by using finite element method. Local analysis will be carried out to capture the stress concentration factor and stress distribution near the high stress location. Miners rule will be used for fatigue damage calculation with the help of the S-N diagram of the respective material used in the structure.