论文标题
飞机机场的水降落阶段的流体动力分析以恒定的速度和固定态度
Hydrodynamic analysis of the water landing phase of aircraft fuselages at constant speed and fixed attitude
论文作者
论文摘要
在本文中，使用不稳定的雷诺（Reynolds）平均的Navier-Stokes（Urans）级别流量求解器$χ$χ$ NAVIS研究了代表三种不同类型飞机主体的机身机身的流体动力学，以恒定的速度和固定态度移动。 CFD研究的目的是洞悉飞机紧急沟渠的水着陆阶段。详细分析了湿表面上的压力变化以及自由表面的特征，显示了三种形状在前面产生的薄喷雾的构型方面的明显差异。这种差异是机身体的不同横向曲率的结果。此外，可以观察到在后方，在发生纵向曲率的变化的情况下，就会形成负压（即低于大气值）的区域。这会产生纯流体动力起源的吸力（向下）。为了更好地了解纵向曲率变化在载荷上的作用，在研究中还考虑了后方的第四个机身形状。作用在机身模型上的力被认为由三个术语组成：粘性，水动力和浮力贡献。为了验证，将数值模拟得出的力与实验数据进行了比较。
In this paper the hydrodynamics of fuselage models representing the main body of three different types of aircraft, moving in water at constant speed and fixed attitude is investigated using the Unsteady Reynolds-Averaged Navier-Stokes (URANS) level-set flow solver $χ$navis. The objective of the CFD study is to give insight into the water landing phase of the aircraft emergency ditching. The pressure variations over the wetted surface and the features of the free surface are analysed in detail, showing a marked difference among the three shapes in terms of the configuration of the thin spray generated at the front. Such a difference is a consequence of the different transverse curvature of the fuselage bodies. Furthermore, it is observed that at the rear, where a change of longitudinal curvature occurs, a region of negative pressure (i.e. below the atmospheric value) develops. This generates a suction (downward) force of pure hydrodynamic origin. In order to better understand the role played by the longitudinal curvature change on the loads, a fourth fuselage shape truncated at the rear is also considered in the study. The forces acting on the fuselage models are considered as composed of three terms: the viscous, the hydrodynamic and the buoyancy contributions. For validation purposes the forces derived from the numerical simulations are compared with experimental data.
