飞机波浪水面迫降过程中极限冲击载荷数值研究

针对飞机在波浪水面迫降过程中机身所受的极限冲击载荷大小及其物理成因问题，采用数值模拟方法展开研究，结合有限体积法和流体体积（VOF）法捕捉自由面，采用六自由度（6DOF）模型和整体运动网格（GMM）处理水面与飞机之间的相对运动，模拟飞机的迫降过程。通过选择飞机相对水面下沉速度最大的波面相位作为迫降触水位置，预报机身所受的极限冲击载荷大小。结果表明:在波浪水面迫降的触水阶段中，机身遭遇了平静水面未预见的冲击峰，同时冲击峰值大小与飞机相对水面的下沉速度有关。此外，对比了在5种不同波高海况下飞机迫降的运动姿态和过载变化历程，给出了波高对极限冲击载荷和其余各参数峰值的影响规律，为飞机载荷分布设计提供参考依据。 

Numerical study on maximu mimpact load during aircraft ditching on wave surface

This paper uses numerical methods to study the magnitude of the maximum impact load on the fuselage and its physical cause during the compulsory landing of the wave. In the numerical calculation, the finite volume method and Volume of Fluid (VOF) method are used to capture the free surface. The Six-Degree-of-Freedom (6DOF) model and the Global Motion Mesh (GMM) are used to process the relative motion between water and the aircraft, and simulate the forced landing process of the aircraft. By selecting the wavefront phase of the aircraft that has the maximum sinking speed relative to the water surface as the position of the forced landing water contact, the ultimate impact load on the fuselage is predicted. The results show that during the water-impacting stage of the wavy surface, the fuselage encounters an unforeseen impact peak on a calm water surface, and the magnitude of the impact peak is related to the sinking speed of the aircraft relative to the water surface. This paper also compares the movement attitude and overload change history of aircraft forced landing under five different wave height sea conditions, and gives the influence rules of wave height on the maximum impact load and the peak values of other parameters, which provides a reference for the design of aircraft load distribution.