Research On Crash Characteristics Of Typical Aircraft Fuselage

Crashworthiness refers to the ability of civil aircraft to protect the occupants in the event of a crash,and is one of the important indicators of civil aircraft safety.This paper investigates the influence of different impact velocities,different impact attitudes and different impact surface conditions on the crashworthiness of a typical fuselage section of a transport aircraft based on the experimentally validated finite element model.By using a combination of experimental and simulation methods,the experimentally validated luggage finite element model is studied and established.The impact of different cargo loading on the crash characteristics of the fuselage section is investigated,in order to provide a reference for aircraft structural crashworthiness analysis and evaluation.The main research contents of this paper are as follows.1.Based on the verified finite element model of a typical fuselage section of transport aircraft,the crash simulation analysis was carried out under different impact velocities,different roll angles and different pitch angles,and the influence law on the deformation pattern and acceleration response of the fuselage section was analyzed.The impact velocity was positively correlated with the deformation severity of the fuselage frame section and the acceleration response at the seat rail of the cabin floor,and the roll angle and pitch angle affected the fuselage deformation position,but the effect on the acceleration response was not significant in the range of 3° to 9°.2.The dynamic impact tests of two different luggage were carried out to study their compression characteristics and acceleration response characteristics under different impact velocities,and a material model was constructed to characterize the stiffness and damping characteristics of the luggage.The effects of cargo loading,different cargo loading amounts and cargo loading methods on the crash characteristics of the fuselage frame were studied.The cargo loading significantly changes the deformation pattern of the fuselage frame section,and the cargo absorbs a large amount of crash energy to reduce the energy absorption burden of the fuselage structure.When the cargo loading is less than 50%,the effect of cargo on fuselage acceleration is small.When the cargo loading is more than 50%,the cargo acts as a conductor of the impact load,which increases the acceleration overload at the passenger cabin floor.3.The crash simulation of the fuselage frame section under different impact surface conditions(rigid ground and soft ground)was carried out,and the deformation pattern of the fuselage frame section obtained from the simulation was relatively consistent.At 6m/s impact velocity,the acceleration peaks at the seat rails of the cabin floor were similar for different impact surface conditions.At 9.14m/s impact velocity,the acceleration peaks at the seat rails of the cabin floor under the soft ground condition are significantly reduced,and the soft ground absorbs part of the impact kinetic energy,which reduces the energy absorption burden of the fuselage structure.