A Review of Research on the Vacuum Plume

Abstract

Chemical and electrical thrusters are generally utilized to control the attitude and orbit of spacecraft in aerospace. When they are firing, the exhaust expands into the vacuum environment, known as the vacuum plume. The plume flow can collide with spacecraft surfaces due to sufficient expansion, exerting adverse effects on the spacecraft, such as heating load, force/torque, contamination, and sputtering. Therefore, it is vital to investigate the vacuum plume to ensure the function and safety of the spacecraft. This review introduces the ground test and numerical simulation methods of the vacuum plume for chemical and electrical thrusters. The vacuum environment, invasive, and non-invasive (optical) measurements of the ground test are concluded. Numerical simulation of plume flow and its effects is exampled. The hybrid CFD-DSMC (computational fluid dynamics and direct simulation Monte Carlo) algorithm is employed to simulate the gas plume flow spanning continuum and transitional and free molecular flow regimes for chemical thrusters. By contrast, the PIC-DSMC (particle-in-cell plus direct simulation Monte Carlo) algorithm is used for the plasma plume flow containing charged particles exhausted by electrical thrusters. Moreover, the topics of fast prediction of the vacuum plume, plume–surface interaction, and plume–Lunar/Mars regolith interaction are proposed for future research.

RETRACTED: Effect of Fluoride Layer Growth on the Deposition Rate under Different Microchannel Structures

“…The molecular free path (λ) was calculated as λ = ( 2 true( 5 − 2 ω true) true( 7 − 2 ω true) 15 ) ( μ ρ ) true( m 2 π k T true) 1 / 2 where ω is the temperature coefficient of viscosity, m is the atomic mass, k is the Boltzmann constant, T is the temperature, μ is the gas dynamic viscosity, and ρ is the gas density. Ensuring that the mesh size was a fraction of the free path, the time-step size was a fraction of the average collision time, and the average number of particles per cell was 25 . A variable hard sphere (VHS) collision model was used. , The Maxwell wall condition, which is suitable for rarefied flow interaction, is used .…”

Rarefied flow regime of an underexpanded supersonic jet

“…Interest in the study of rarefied regimes of interaction of supersonic jets with the environment is associated with the development of aerospace applications and vacuum technologies. Evaluation of the parameters of rocket engine jets flowing into a rarefied space is necessary when designing spacecraft in order to exclude the harmful effects of the jet on the spacecraft surfaces [1]. In vacuum gas jet technologies for the synthesis of nanomaterials, the parameters of the outflow of a highly underexpanded jet predetermine the conditions for the formation of clusters in the volume of the gas phase, and in the case of the growth of a nanostructured film directly on the sprayed surface -the rate of deposition of the material on the substrate [2].…”