含货舱门的大型民机机身段垂直坠撞仿真分析
Simulation and Analysis on Vertical Crash of Civil Aircraft Fuselage Section with Cargo Door

建立了含货舱门的大型民机机身框段结构适坠性分析的全尺寸非线性有限元模型，模型中考虑了机身框、长桁、蒙皮、货舱及行李、客舱地板、客舱吊柜和座椅。利用该模型对机身框段进行了垂直坠撞仿真分析，坠撞速度为9.14 m/s，采用动力学软件MSC.Dytran进行求解，计算得到机身框段结构的变形和试验中各测量点处的加速度响应。计算结果与试验结果的吻合验证了所建模型的有效性。在该模型的基础上，对机身框段在不同滚转角垂直坠撞工况下的适坠性进行了分析。结果表明：在所计算的工况中，当飞机左滚12°和右滚8°坠撞时，机身结构破坏最严重，乘员承受的过载最大。货舱门结构增加了舱门侧的机身结构刚度，使机身结构左右变形不对称，含舱门侧的机身变形较小，含舱门侧的乘员承受过载较大。
A full-scale nonlinear finite element model (FEM) was developed to obtain the crash performance of civil aircraft fuselage section. The FEM included the cargo door structures, as well as the airframes, skins, luggages, overhead baggage bay and seats in cabin. The FEM was used to simulate the vertical crash of the aircraft fuselage section. The initial impact velocity of the fuselage section was 9.14 m/s. The FEM was solved in MSC.Dytran and exported the deformation results of the fuselage section and the acceleration of all the measure points defined in the corresponding experiments. The FEM was validated by the agreement of the simulation results and the experiments data. The dynamic responses of the fuselage section with different roll angles were calculated with the validated FEM in the same initial velocity. The simulation results show that the damage of fuselage structures was most severe and the overloads of the passengers were largest in both cases of roll left 12° and roll right 8°. The deformation of the right hand side (RHS) fuselage was smaller than the left hand side (LHS) fuselage because the stiffness of the RHS fuselage structures was increased by the cargo door structures. The overloads of passengers on the RHS seats were also larger than the LHS due to the cargo door structures