Numerical Study of Wave Effect on Aircraft Water-Landing Performance

Abstract

Aircraft, such as amphibious planes, airliners, helicopters and re-entry capsules, are frequently subject to impacting loads from water-landing/ditching on various free surfaces, especially under wave conditions. Understanding and quantifying the water-landing/ditching performance on wave surfaces are of fundamental important for the design and certification of crashworthiness in the field of aerospace engineering. This study aims to numerically assess the effect of wave surface on water-landing process of an amphibious aircraft. The numerical implementation is realized in Reynolds-averaged Navier–Stokes (RANS) framework by combining finite volume method (FVM), volume of fluid (VOF) approach and velocity-inlet wavemaker. The temporal-spatial characteristic of numerical wave and the accuracy of presented model are, respectively, validated by analytical wave and convergence studies. The aircraft landing simulations with different free surface conditions, i.e., calm water, regular wave with different wave heights are then performed and quantitatively compared through several physical parameters, including acceleration, velocity, pressure, pitch angle and free surface deformation. It was found that the aircraft regular wave-landing process experiences several unique stages comparing with the calm-water-landing case. The results clearly confirm that wave surface can influence the aircraft landing performance to a great extent. The fundamental mechanism is found to be that the wave surface slope and wave particle velocity remarkably change the impacting position and effective impacting velocity of the aircraft.

Numerical Simulations of Seaplane Ditching on Calm Water and Uniform Water Current Coupled with Wind

“…It is also needed to specify how the grids move relative to each other according to the movement of the wall boundary of the solid body. The Dynamic Fluid-Body Interaction (DFBI) model [31] allows for the solution of body motions in case mobility is not predetermined. The object's movement, resulting from the influence of fluids and other forces, is transmitted via the overset mesh.…”

Numerical analysis of influencing factors on wave load for an amphibious aircraft

“…Ma Zenghui used ALE (Arbitrary Lagrange-Euler) method to describe the computational fluid domain, used penalty function coupling method to describe the coupling between aircraft and water body, and studied the motion response of aircraft taking off and landing on different wave surfaces and the dynamic characteristics of fuselage bottom pressure [1]. Chen and others systematically studied the landing performance of amphibious aircraft in waves using RANS equation combined with FVM and VOF methods [2]. Li Xinying carried out numerical simulation research on seakeeping of the hull of an amphibious aircraft based on the sliding grid method, and compared with the model test results to verify the reliability of the method [3].…”