Fatigue Simulation Analysis Of B737 Nose Landing Gear Structure Considering Crosswind Effect

With the improvement of the national material living standard,people get more likely to choose airplane for travel,so the society pays more and more attention to flight safety.To be able to take on more missions,the aircraft will need to adapt to a harsher service environment.The landing gear system,as one of the few non-redundant systems on the aircraft,is particularly required to ensure the structural safety under the complex load conditions.With the increasing service life of civil aircraft in China,the possibility of fatigue failure of aircraft structure is also increasing.Under the new situation of landing gear structure safety,it is of great significance to accurately predict the fatigue life of landing gear under complex external load conditions.In this paper,the fatigue life simulation analysis of the structure of B737 nose landing gear was carried out considering the influence of crosswinds.The effects of crosswinds on the fatigue life of B737 nose landing gear were revealed.The ground motion law of the aircraft was analyzed,and the mechanical analysis model of the aircraft was established by using the basic mechanical equation.And the ground load of nose landing gear under different positive crosswind wind speeds was calculated by taking B737 as an example.A three-dimensional finite element model of the B737 nose landing gear was established based on the simplified technology.Considering the ground load under different cross-wind speeds,the static analysis based on the finite element method was carried out by using ANSYS software.The fatigue load spectrum of B737 nose landing gear was determined,and the fatigue life of B737 nose landing gear was analyzed by considering different crosswind wind speed conditions.The main content of this paper is as follows:1.The kinematics and dynamics model of the ground motion of the aircraft was established.Taking the data of B737 model,the ground load of the nose landing gear in the ground motion of B737 aircraft was calculated under the conditions of different crosswind wind speeds.2.based on the finite element theory,the B737 before landing gear structure reasonably simplified,and the corresponding three-dimensional finite element model was established.Considering the boundary conditions and load conditions of the model,the professional finite element software ANSYS was used to simulate the structure of B737 nose landing gear.The stress state of B737 nose landing gear under the action of crosswind with different wind speeds was obtained,and the influence of crosswind on the stress distribution of B737 nose landing gear was revealed.3.Based on the fatigue cumulative damage model,the fatigue life of B737 nose landing gear was analyzed by using the professional fatigue analysis software n Code,and the influence of crosswind on the fatigue life of B737 nose landing gear was analyzed.