Aeroelastic Analysis Of High-speed Train Structures

With the increase of train speed, the interaction between the train and air ismore and more obvious. Consequently, the aeroelastic problems for the high-speedtrain structure are studied in this thesis. The main contents are as follows:On the background of skirtboard in high-speed train, the aeroelastic equation oftwo-dimensional cantilevered plate whose one surface is subjected to the subsonicair flow is established using the classical thin plate theory and the aerodynamicforce model based on the linear potential flow theory. The equation of motion isdiscretized to the ordinary differential equations by using Galerkin’s method. Theflutter characteristics are analyzed by solving the generalized eigenvalue problem,and the responses of the plate in time domain can be calculated by the Newmarknumerical integration method. Numerical simulation shows that the flutterphenomenon can occur for thin plate subjected to subsonic air flow. The vibration ofthe plate can be convergent for the air flow speed being below the critical flutterspeed, while it can be divergent for the air flow speed above the critical flutter speed.If the air flow speed is equal to the critical flutter speed, the constant amplitudevibration will appear.The CFD/CSD algorithm which is a two-way fluid-structure coupling algorithm,is used to solve the responses of cantilevered plate in this thesis. The responsesobtained by the CFD/CSD are compared with those calculated by theoretical method.The results calculated by both methods are in good agreement with each other,which indicates that the CFD/CSD algorithm is appropriate to solve the aeroelasticproblem. Three-dimensional plate structures with different boundary conditions,such as cantievered, simply supported and clamped plates are considered. Thevariation of flow field distribution and the displacement responses of plate underdifferent conditions are analysed. Meanwhile, the influences of different structuraland material parameters, such as ribbed and non-ribbed structures, steel andaluminum alloy plates are considered.For the research on the responses of trian structures under aerodynamic force,this thesis is different from traditional research method. The interaction betweenelastic deformation of train structure and aerodynamic force is the main focus of thisthesis, and the body motions of the train will be ignored. Through the CFD/CSDalgorithm, the flow field distribution around the train and the responses of differentparts in the train structures are analysed.The research in this thesis can provid an effective method in the reaserch on the aeroelastic analysis for high-speed train structures.