Gravity-Assisted Two-Phase Radiator Architectures for Rotating Artificial-Gravity Habitats

Companion research manuscript presenting a gravity-assisted, two-phase natural-circulation radiator architecture for rotating artificial-gravity habitats. The system exploits centrifugal fields to enable passive phase separation, hubward vapor transport, rimward condensate return, and hydrostatic driving head without mechanical pumping. A metric-first formulation is introduced, expressing thermal performance as heat rejection per unit active channel length. Under representative conditions, the architecture supports approximately 420 W/m of active channel length, corresponding to ~2.4 km per MW of electrical dissipation. A representative 2.7 MW sector requires ~6.5 km of active channel, which is shown to be geometrically and hydraulically compatible with a rotating habitat wedge. The work demonstrates architectural closure across thermal, geometric, and hydraulic constraints, positioning the concept as a rotating-environment-specific alternative to conventional spacecraft thermal control systems.