Saumya Ranjan

PhD Thesis

Numerical modeling and analysis of air-breathing electric propulsion thrusters for LEO drag compensation.

Supervisors

Jiewei Zhu Zhu (UC3M) & Ahilan Appar (UC3M)

Abstract

Very Low Earth Orbit enables high-resolution Earth observation, low-latency communications, and emerging in-orbit services, but persistent atmospheric drag severely limits mission lifetime. Atmosphere-breathing electric propulsion offers a disruptive solution by collecting residual atmospheric species and using them directly as propellant, eliminating onboard propellant storage. However, current ABEP prototypes exhibit low efficiency, and existing modeling approaches treat the intake and plasma thruster separately, relying on simplified gas surface interaction models and incomplete air plasma chemistry.
This PhD thesis aims to develop a self-consistent, two-way coupled numerical framework that integrates intake flow and plasma discharge within a unified simulation tool. The in-house hybrid code HYPHEN will be extended to incorporate atomic-based, material-dependent gas/plasma surface interaction models and an expanded multispecies air chemistry including heavy-species reactions and multiply charged ions. The upgraded tool will quantify intake mass flow under realistic orbital conditions, analyze discharge physics for representative Hall and RF ion thrusters, and determine optimal operating regimes for VLEO drag compensation.
The expected outcomes include the first comprehensive intake–thruster coupled characterization of ABEP systems, identification of dominant efficiency and loss mechanisms, and the delivery of an advanced simulation platform to support future prototype design. This research will strengthen UC3M’s leadership in electric propulsion and contribute to the technological maturation of sustainable VLEO missions.