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Thermal destruction of aircraft structure caused by aerodynamic heating is one of the hidden troubles to the vehicle safety. To predict the structure temperature field of hypersonic vehicle accurately is very important for the thermal protection system design. Coupling methods of aerodynamic heating and heat transfer, and corresponding engineering applications have been carried out in a lot of works worldwide up to date. However, the influence of structural deformation on aerodynamic heating and structural temperature field was generally ignored in many of these studies. In an actual flight, especially after a long-time flight, the structural deformation caused by the coactions of aerodynamic and temperature rise has some direct impact on the aerodynamic heating and structural temperature field, and needed to be taken into account. In this paper, coupling effects of aerodynamic heating and heat transfer on a hypersonic aircraft wing model were investigated considering the influence of aerothermoelasticity deformation based on static aerothermoelasticity analysis method. The results show that, for the great mass of region, deformation of thermal structure has inconspicuous effect on temperature field, structural stress and strain. Nevertheless, for the region near to the stagnation point and leading edge, where the key regions of thermal protection system design, the calculation results change obviously. Therefore, during the solution process concerning aerodynamic and structural thermal coupling effect, the decoupling method can be considered to reduce the calculation cost when aeroelastic deformation is small. The present work lays the foundation for improving the prediction accuracy of the temperature field of aircraft structures and structural performance evaluation capacity. [ABSTRACT FROM AUTHOR]

The combustion of carbon-based materials in a high speed stream of dissociated air is analyzed, together with the oxidation mechanism from reaction rate controlled regime through the transition to diffusion controlled oxidation. The product of the heterogeneous reaction of carbon with oxygen is known to be CO and CO2, and CO2 is generally usually neglected when surface temperature is higher than 1000K in many literatures. However, we find that CO2 plays an important role in the whole oxidation processes, and can't be ignored through the three regimes. It is shown that two different platforms existed in the diffusion controlled regime. The first platform results from a reaction of the predominant CO2 product, and the other is due to the predominant CO product reaction. In fact, the concepts of "fast" reaction and "slow" reaction are not proper, since the two are the extreme cases of the general model we proposed. As surface temperature rises, the oxidation process will change automatically from nominated "fast" reaction to " slow" reaction. The dual platform theory has been confirmed by several experimental results. [ABSTRACT FROM AUTHOR]

Uptodate, multi-objective optimization is widely adopted in the field of hypersonic vehicle configuration design. Generally speaking, aerodynamic characteristics are determined by the vehicle configuration, and the capability of completing the flight missions is determined by the design of flight trajectory. In this paper, the parametric geometrical configurations are proposed, and the aerodynamic characteristics are predicted by the rapid and effective engineering method. The configuration is optimized to satisfy the design goals of maximum lift-to-drag ratio and maximum volume utility ratio simultaneously. And the optimization of flight trajectory design considering the integration of aerodynamics and aerothermodynamics is investigated based on a given configuration example. The detailed research indicates that the optimal configuration and flight trajectory obtained by the optimization can fulfill the requests of the designers, and the results can be used as the feasible schemes in the future work. This research has a very obvious background of engineering application and value of application extension. [ABSTRACT FROM AUTHOR]

Ice formation on aircraft is of great safety concern because icing may lead the aircraft to a dangerous situation quickly. Numerical method for determining the trajectories of the water droplets is the base of the icing research and the design of the anti-icing system. The traditional Lagrangian method for simulating water droplet trajectory and impingement has some shortages such as lower computation efficiency and poor applicability currency in peculiar geometry. In order to overcome these shortages, an improved Lagrangian method was developed. It's based on the calculation of the flow field around icing surface, using a method of searching extended target to calculate the droplet location and determining the insert value of flow field information at the droplet location in a grid cell, the boundary of the droplet trajectories are judged based on a manage system of boundary information with framework structure. The method can overcome theses shortages meanwhile maintains the robustness of original method. Local droplet collection and impingement efficiency at NACA0012 and multi-element airfoils are calculated with this method in order to verify its correctness. The results show that the improved method is very efficient, reliable, and robust. Furthermore, it can be used in different geometries directly. [ABSTRACT FROM AUTHOR]

The Crew Space Transportation System (CSTS) is a proposed next generation manned exploration vehicle which will transport crew both to the ISS in Low Earth Orbit, and to Low Lunar Orbit. In this paper, orthogonal numerical experiment with four factors and three levels was arranged, using the orthogonal experimental design method. The influence of geometric parameters on the aerodynamic characteristics was discussed, aiming at finding the configuration with the highest L/D value. After selecting the configuration, the trim L/D line was found out for the required L/D. The placement of the center of gravity on the trimline which affects the pitch static stability and the aerodynamic sensitivity to the placement was investigated for better aerodynamic perfermance. [ABSTRACT FROM AUTHOR]

The computational means are developed to predict the radiative heating influence of high-temperature nonequilibrium gas on the aerothermal enviroment in order to meet the requirement of aerothermal enviroment understanding over hypersonic reentry vehicles. The high-temperature air flowfield over a reenrty capsule after the lunar-earth transfer orbital flight are simulated by solving Navier-Stokes equations with chemical source terms, the parameters, such as temperature and mass fraction of species in the flowfilds, are obtained. Based on radiation transfer equation, considering the major radiative mechanisms of atoms and molecules in high temperature air, radiative heating influences on aerothermal environment of reentry capsule are studied numerically. The investigation indicates that the nose radius of the capsule has significant influence on aeroheating with the given trajectory condition, and the radiative heat flux at local surface contributes over 30 percent of the total heat flux for those mostly severe aero-heating region. It also shows that catalytic effects on radiative heat flux is not so evident, the major radiative sources are the continual and line spectra of O and N, together with the first positive band of N2. [ABSTRACT FROM AUTHOR]