Study On New-Typed High-Temperature Endurable Multilayer Insulation

Space vehicles will suffer both serious aerodynamic force and aerodynamic heating when they are flighting. So design of thermal protection and heat insulation for space vehicles is necessary, on the premise of aerodynamic force, which will protect re-entry module from burning by aerodynamic heating, make the fuselage and interior parts work normally under the appropriate rage of temperature. Advanced Thermal Protection System (TPS) is strongly expected to be developed as one of the key technologies of space vehicles. High-temperature heat insulations with high efficiency and lightweight is an absolutely necessary part of Thermal Protection System.Heat transfer mechanism in the multilayer insulation (MLI) is analyzed firstly in this thesis. A new-typed high-temperature endurable multilayer insulation (MLI) comprised of alumina silicate fiber-papers, silica fiber net, hydrophobic silica aerogel granules as a kind of fillings is developed by felting process. It's most different character from other multilayer insulations is that aerogel granules as known as the"super thermal insulations"are mixed into the binder. Because of the aerogel granules here as a kind of heat insulation filling with a low thermal conductivity, the binder has the performance of heat insulation.Firstly, studies on elements of the new-typed high-temperature endurable multilayer insulation are carried out. SEM, TG-DTA, XRD and IR are respectively used to analyze the alumina silicate fiber-papers, silica fiber net, hydrophobic silica aerogel granules. Then the performances of their insulation and heat-resistant stabilization are discussed through the above testing results. The process of filling in high-temperature adhesive is developed after repeated experiments. The relationship between the new-typed high-temperature endurable multilayer insulation and the quantity of fillings is discussed through changing the quantity of fillings. SEM is used to figure the microstructure of adhesive with fillings. Then the effects of dispersion and felting as well as the performance of insulation are discussed according to the SEM photos. Lastly, the adiabatic performance of new-typed high-temperature multilayer insulation is tested respectively by Quartz Lamp Heating Device and PBD-02P Table Thermal Conductor.The results show that the new-typed high-temperature endurable multilayer insulation made in this thesis can be used chronically under the temperature of 800℃to 1000℃. Its density is always less than 250kg/m3. The effective thermal conductivity of this new-typed high-temperature endurable multilayer insulation is 0.065W/(m·K) at 800℃and 0.080W/(m·K) at 1000℃respectively. It'll be widely used in the fields of aeronautical and space technologies because of its excellent allround properties.