Journal of Applied Polymer Science, EarlyView.
By taking the coupling ablative mechanism into consideration, a multi‐field coupling model with key influencing factor to evaluate material responses and chemical responses in boundary layer is developed and numerically solved by our coupling calculation strategy. By designing the distribution of key factor along material thickness, a gradient design for charring composite is given and shows good ability to control temperature and amount of surface ablation recession.
With the development of hypersonic vehicles, reentry vehicles are facing a more severe aerothermodynamic heating environment. It is necessary to design high‐efficiency charring composite used as the heat shield in the thermal protection system (TPS) of reentry vehicles. By taking the material responses (volume‐surface coupled ablation), exothermic gas‐phase reactions of pyrolysis gases in the boundary layer and the flow behavior of chemical nonequilibrium inflow coupling ablative mechanism into consideration, a developed thermal/fluid/chemical/ablation coupling model with the key influencing factor on thermal protection performance of charring composites is built to evaluate the material responses and the chemical responses in boundary layer near its surface. Based on this model, the key factor (fiber volume fraction) influencing on the thermal protection performance is analyzed by using a coupling numerical calculation strategy. By designing the distribution of this parameter along the thickness of the material, a gradient design for charring composite is given. The numerical results indicate that the gradient charring composite can control the temperature distribution and the amount of surface ablation recession. This study will be a guidance for the design of charring composites for thermal protection application in reentry vehicles in a quantitative and efficient manner.