Study On Thermal Response Characteristics Of High - Speed Aircraft Structures

High-speed aircrafts must be subject to the impact of aerodynamic heating when fly in the atmosphere for a long time. Take the winged aircraft as the research object and the thermal response characteristics of the aircraft structure is studied, which can provide reference data for the design of the aircraft structure. The thermal response analysis of aircraft structure includes temperature field calculation, thermal stress analysis, thermal deformation analysis and thermal modal analysis.Firstly expounds the basic principle of computational fluid dynamics to solve the problem of aerodynamic heating, and use the ICEM software to meshing the aircraft model, and established aerodynamic models of high-speed aircraft in the FLUENT software. Analyze the aerodynamic heating effect, under different working conditions, which provides initial conditions for the thermal response analysis of the aircraft structure.The coupled heat transfer models of fluid and vehicle are established on the basis of steady flow field, and adopt the method of coupled heat transfer to calculate the transient heat transfer process of aircraft structure under different cases. Analyze the temperature field distribution characteristics of aircraft structure in different flight Mach number, different flight time and different flight angle of attack.According to the thermal elastic mechanics and finite element method, the aircraft finite element model is established. Use the ANSYS Workbench platform of finite element, and apply the pre-computed temperature field on the finite element model of the aircraft to calculate the thermal response characteristics of aircraft structure under different thermal load.Analyze the thermal modal characteristics of aircraft empennage by using finite element method. the thermal modal characteristics of the wing structure under three conditions are calculated, and compared with the modal characteristics of normal temperature, to analyze the changing regularity of modal parameters with the temperature change, and at last the influence degree of the variable physical parameters and thermal stress on modal characteristics are discussed.