Efficiency Metrics and Numerical Simulation Procedure for Atmosphere-Breathing Electric Propulsion (ABEP) Intake Designs

The intake of an atmosphere-breathing electric propulsion system plays a pivotal role in capturing and collimating atmospheric residuals prior to the propulsion stage. Accurate assessment of intake performance necessitates accounting for rarefied gas dynamics, flow compression, and gas-surface interactions. In this study, the DSMC solver, dsmcFoam, is rigorously validated against fundamental benchmarks, including Clausing empirical cases and comparisons with the PICLas solver. Furthermore, dsmcFoam-dsmcFoam comparison is also conducted and observed deviations between our results and existing dsmcFoam results in the literature highlight the critical importance of careful simulation setup and procedural rigour. A systematic analysis of the simulation workflow, supplemented by additional computational strategies, demonstrates their pronounced impact on intake performance metrics. Furthermore, distinct definitions for efficiency—namely, collection efficiency and transmission efficiency for vacuum, standalone, and integrated configurations—are introduced, establishing a comprehensive framework for evaluating intake performance across varying operational altitudes and surface properties. The findings confirm that (i) dsmcFoam represents a reliable tool for ABEP intake design, providing a foundation for further developments, (ii) a structured and generic simulation procedure tailored for ABEP intakes is essential, and (iii) conventional efficiency metrics for ABEP intakes needs reconsideration for broader applicability and accurate performance evaluation. • Verification of dsmcFoam for ABEP intake simulations. • Additional recommendations for the ABEP intake simulation procedure. • Discussion on efficiency metrics of ABEP intake.