Search

The vertical gap flow in the wing-leading-edge of the hypersonic vehicle is investigated in this paper. By analyzing the structure of the leading-edge shield, a geometrical model for the leading-edge gap is established. The flow field structure is obtained by solving the 3D Navier-Stokes equations. The spatial distribution fetature of the 3D vortex induced by gap and corresponding relations between the vortex motion and heat-flux distribution are analyzed. The numerical result shows that in the circular section, the rounding zone of the gap shoulder is a local high heat flux region because of strong 3D-effect normally, and the reattachment of the primary vortex in the gap leads to a "non-normal" high heat flux region on the side wall of the gap. In the straight section, there is a strong vortex region above the gap induced by span wise flow. Because of the effect of vortex separation, the original local high heat flux region at the rounding zone of the gap shoulder turn to local low heat flux region, and local high heat-flux region exists in the side wall region. [ABSTRACT FROM AUTHOR]

Three-dimensional compressible Navier-Stokes equations are numerically solved for the 70° sphere-cone heatshield to predict the hypersonic chemical non-equilibrium aeroheating with catalytic effects. Numerical results show that a substantive amount of inflow gas dissociates in the shock layer, which causes chemical non-equilibrium flow with remarkable high-temperature real-gas effect, particularly near the stagnation. The surface catalysis markedly influences the total heating load, and the heatfluxes for non- and fully catalytic walls are predicted to bear the lowest and highest aeroheating bounds. The determination of O2 and CO2 recombination is expected to be the significant sources of the catalytic heating, and the characterization of the catalytic mechanism of the thermal protection materials is needed so as to precisely predict the Mars entry aeroheating. [ABSTRACT FROM AUTHOR]