Modeling Of Platelet Sodium Medium Heat Pipe For Aerothermal Heating Dredging Of High Speed Airfoil

Hypersonic vehicles will face severe aerodthermal heating during the flight, which will make the temperature of the structure very high, and the high temperature will debase the intensity and destroy the aerodynamic shape of the structure or even make the structure burned. Heat pipe dredging thermal protection structure is a kind of half-passive thermal protection mechanism. It can transfer the high heat flux of the leading edge to the low temperature area rapidly. Then the severe aerodthermal heating can be released by the convection or radiation of the wing.In allusion to the dredging hermal protection of hypersonic vehicles in typical flight mode, this paper has demonstrated the feasibility of using heat pipe structure and designed a kind of integrative platelet heat pipe structure with natrium as working medium. This paper has taken one heat pipe unit of the designed platelet heat pipe structure as the research object, and derived the working limit equations of the heat pipe. Then this paper has given a concrete analysis about the effect of the acceleration on the designed heat pipe structure. To explore the mechanism of dredging thermal protection of the platelet heat pipe, this paper has established the physical and mathematical models of the axial flow and heat transfer of the heat pipe unit in the structure based on the reasionable predigestion and hypothesis, and got the distribution of the internal parameters and surface temperature of the heat pipe through the four order Runge-Kutta method. And the calculation data accord with the experimental data in the literature. Depending on the anterior modeling, this paper has imported the pneumatic thermal data of the leading edge to the axial flow and heat transfer model, and got the pressure and flow distribution of the internal sod ium medium and the surface temperature of the heat pipe which works in a steady state through the method of iterative algorithms. To validate the reliability of calculation and the leading thermal protection performance, this paper has used the equivalent heat transfer coefficient method of the heat pipe to calculate the temperature distribution of the 3D leading edge structure as a reference basis, and analyzed the main source of the calculation error. Based on the model of heat analysis, this paper has analysed the influence of the surface blackness of the heat pipe struture on aerodthermal heating dredging.