Pressure-Driven Combustion and Re-Ignition of Electrically Controlled Solid Propellant

Electrically controllable solid propellants (ECSPs) enable plug-and-play thrust for small satellites by removing pyrotechnic igniters and pressurized feeds. This study examines the pressure-coupled combustion of a hydroxylammonium-nitrate/polyvinyl-alcohol (HAN/PVA) ECSP over 0.1–5.0 MPa. Electrochemical ignition tests recorded flame luminosity, surface regression, and electrical response. Two burning-rate regimes were observed: below 1.5 MPa, [Formula: see text]; above 1.7 MPa, [Formula: see text], reaching [Formula: see text] at 5 MPa. The breakpoint corresponds to a pressure-induced transition in the dominant condensed-phase combustion mechanism, distinct from the ECSP’s low-pressure deflagration limit ([Formula: see text]). Ignition delay decreased from 2.1 s at 0.1 MPa, converged to 0.4 s above 1 MPa. Extinction became pressure-limited, with a 0.1 s post-cutoff tail at 4.7 MPa. Re-ignition at 0.4–0.8 MPa required [Formula: see text] less power and exhibited [Formula: see text] higher burning rates due to residual heat and conductive melt. These results confirm rapid, repeatable ignition, pressure-tunable thrust, and reliable self-extinguishment, demonstrating the viability of HAN-based ECSPs for pulsed or throttled microthrusters and providing key design data for future satellite propulsion systems.