When a vehicle with rotation reenters the atmosphere in an angle of attack, it will experience an alternating heat flux on the upper surface of the thermal protection farer. Andthe position of maximum temperature on t...When a vehicle with rotation reenters the atmosphere in an angle of attack, it will experience an alternating heat flux on the upper surface of the thermal protection farer. Andthe position of maximum temperature on the surface is not coincident with that of maximum heat flux, which is called thermal retardation. In this paper, the thermal retardationphenomena of the thermal protection layer under an alternating heat flux are numericallysimulated. The effects of many factors, such as the time of heating, the angular velocity ofthe rotation and the properties of thermal protection material, are researched on the thermalretardation. Which is useful to the design of thermal protection layer of vehicle.展开更多
The energy equilibrium equation and discrete ordinate methods are combined to establish the one-dimensional steady heat transfer mathematical model of multi-layer thermal insulations (MTIs) in metallic thermal prote...The energy equilibrium equation and discrete ordinate methods are combined to establish the one-dimensional steady heat transfer mathematical model of multi-layer thermal insulations (MTIs) in metallic thermal protection systems. The inverse problem of heat transfer is solved by the genetic algorithm and data from the steady heat transfer experiment of fibrous thermal insulations. The density radiation attenuation coefficient, the albedo of fibrous thermal insulations and the surface emissivity of reflective screens are optimized. Finally, the one-dimensional steady heat transfer model of MTIs with optimized thermal physical parameters is verified by experimental data of the effective MTI conductivity.展开更多
文摘When a vehicle with rotation reenters the atmosphere in an angle of attack, it will experience an alternating heat flux on the upper surface of the thermal protection farer. Andthe position of maximum temperature on the surface is not coincident with that of maximum heat flux, which is called thermal retardation. In this paper, the thermal retardationphenomena of the thermal protection layer under an alternating heat flux are numericallysimulated. The effects of many factors, such as the time of heating, the angular velocity ofthe rotation and the properties of thermal protection material, are researched on the thermalretardation. Which is useful to the design of thermal protection layer of vehicle.
文摘The energy equilibrium equation and discrete ordinate methods are combined to establish the one-dimensional steady heat transfer mathematical model of multi-layer thermal insulations (MTIs) in metallic thermal protection systems. The inverse problem of heat transfer is solved by the genetic algorithm and data from the steady heat transfer experiment of fibrous thermal insulations. The density radiation attenuation coefficient, the albedo of fibrous thermal insulations and the surface emissivity of reflective screens are optimized. Finally, the one-dimensional steady heat transfer model of MTIs with optimized thermal physical parameters is verified by experimental data of the effective MTI conductivity.