Effect of pitch angle on initial stage of a transport airplane ditching  

作　　者：Guo Baodong Liu Peiqing Qu Qiulin Wang Jiawen 

机构地区：[1]Institute of Fluid Mechanics, Beihang University [2]Key Laboratory of Fluid Mechanics, Ministry of Education, Beihang University

出　　处：《Chinese Journal of Aeronautics》2013年第1期17-26,共10页中国航空学报（英文版）

基　　金：co-supported by Aeronautical Science Foundation of China (No.20102351023);Research Fund for the Doctoral Program of Higher Education of China (No. 20091102120021)

摘　　要：Airworthiness regulations require that the transport airplane should be proved to ensure the survivability of the ditching for the passengers. The planned ditching of a transport airplane on the calm water is numerically simulated. The effect of pitch angle on the impact characteristics is especially investigated by a subscaled model. The Reynolds-averaged Navier-Stokes （RANS） equations of unsteady compressible flow are solved and the realizable j-e equations are employed to model the turbulence. The transformation of the air-water interface is tracked by volume of fluid （VOF） model. The motion of the rigid body is modeled by dynamic mesh method. The initial ditching stage of the transport airplane is analyzed in detail. The numerical results show that as the pitching angle increases, the maximal normal force decreases and the pitching motion becomes much gentler. The aft fuselage would be sucked down by the water and lead to pitching up, whereas the low horizontal tail prevents this trend. Consequently, the transport aircraft with low horizontal tail should ditch on the water at an angle between 10 and 12 as a recommendation.Airworthiness regulations require that the transport airplane should be proved to ensure the survivability of the ditching for the passengers. The planned ditching of a transport airplane on the calm water is numerically simulated. The effect of pitch angle on the impact characteristics is especially investigated by a subscaled model. The Reynolds-averaged Navier-Stokes （RANS） equations of unsteady compressible flow are solved and the realizable j-e equations are employed to model the turbulence. The transformation of the air-water interface is tracked by volume of fluid （VOF） model. The motion of the rigid body is modeled by dynamic mesh method. The initial ditching stage of the transport airplane is analyzed in detail. The numerical results show that as the pitching angle increases, the maximal normal force decreases and the pitching motion becomes much gentler. The aft fuselage would be sucked down by the water and lead to pitching up, whereas the low horizontal tail prevents this trend. Consequently, the transport aircraft with low horizontal tail should ditch on the water at an angle between 10 and 12 as a recommendation.

关 键 词：CRASHWORTHINESS Fluid structure interaction HYDRODYNAMICS Multiphase flow Transport aircraft Water landing 

分 类 号：V271.2[航空宇航科学与技术—飞行器设计] V275.1