Study And Implementation Of Data Transfer Methods For Interfaces Of Fluid-structure Interaction

Fluid-structure interaction analysis is more and more extensively applied in many fields such as aeronautics and astronautics,civil,marine and chemical engineering.It plays a significant role in the safety assessment of various engineering structures.Computation of fluidstructure interaction is complicated and the solution of fluids and structures is very different in algorithm constitution,computational meshes and boundary conditions.For the purpose of simplification as well as reducing the complexity of engineering analysis,computations of fluids and structures are often separated and they are solved independently,but effective data transfer between them is required,in terms of kinematics and kinetics.At the interface of fluid-structure interaction,the computational meshes of fluids and structures are non-matching and the distribution of their computational nodes differs from each other.However,kinetic information should be accurately transferred to the nodes of structures by fluids.Meanwhile,kinematic information should be accurately transferred to the nodes of fluids by structures.Accordingly,the complex fluid-structure interaction analysis is divided into three modules: fluid computing,structure computing and data transfer through the interfaces of fluid-structure interaction.With the aeroelasticity of aviation structures as the research background,this thesis is dedicated to the algorithmic study of data transfer methods and the main work is as follows:（1）The method of constant volume tetrahedron（CVT）is numerically implemented based on in-depth knowledge of its algorithm.Three numerical examples including the HIRENASD wing model are successfully analyzed and the feasibility of the CVT method in data transfer through interfaces is verified.（2）The method of radial basis functions is studied in details and its numerical implementation with compactly supported radial basis functions is conducted.The performance of the method is investigated by the numerical examples,e.g.bending of wings of aircraft.The method of compactly supported radial basis functions for data interpolation transfer through interfaces is validated.In addition,the influence of the radius of the compact support on the computational efficiency is investigated in details.（3）The parallel computing of the method of compactly supported radial basis functions is studied and the corresponding computer program is developed based on the library of PETSc.Numerical example of bending of wings is investigated with parallel computing and the accelerated computation by the developed computer program is demonstrated.The speedup and efficiency of the parallel computing are investigated.The computational time and the number of total iterations with different preconditioners are compared and analyzed.The study of this thesis shows that both the method of constant volume tetrahedron and the method of radial basis functions are able to transfer interface data accurately.In addition,the conclusion about the method of radial basis functions can be summarized as following:（1）Its accuracy improves with increasing the radius of the compact support,but the computational cost also increases;（2）Parallel computing can significantly improves the computational efficiency of the method and it converges faster with the use of preconditioners.