Influence of wall characteristics on intake performance for intake device of atmosphere-breathing electric propulsion system

Abstract

As an emerging space propulsion technology, atmosphere-breathing electric propulsion (ABEP) system can operate for a long time in ultra-low earth orbit (ULEO) without carrying propellant from ground. However, the erosion of intake wall caused by the oxygen-contained atmosphere in ULEO will alter the wall characteristics to some degree, which influences the intake performance significantly. To analyze the influence of wall characteristics on intake performance, the direct simulation Monte Carlo (DSMC) method is used to simulate the gas flow in intake chamber under the mixed inflow of N₂ and atomic oxygen (AO). The density and velocity distribution of flow field for three intake configurations (parabola, cone and cylinder-cone type) are analysed under the varying wall characteristics (reflection coefficient σ from 0 to 1), and the corresponding variations of the collection and compression performance are also obtained. Results show that the increasing of σ leads to the decline of collection efficiency for all three intake configurations. The parabola type intake shows the highest collection efficiency of 93.67% when σ=0 under the specular reflection condition. The compression ratio increases with the value of σ for both parabola and cylinder-cone type, while the compression ratio for cone type intake initially increases then decreases, which reaches the maximum value of 44.36 when σ=0.5.