Effects of Formulation and Electrode Parameters on the Ignition Performance of Electrically Controlled Solid Propellant

This study investigates the effects of flame-retardant fillers, mesh electrode geometry, electrode material, propellant thickness, and applied voltage on the ignition and combustion performance of a perchlorate-based Electrically Controlled Solid Propellant (ECSP). Resistivity measurements show that phenolic resin (BS) increases resistivity by 82.8% (to 78.33 Ω·m), whereas decabromodiphenyl ether (BW) decreases it by 32.3% (to 29.04 Ω·m), relative to the base formulation (42.9 Ω·m). Finite element simulations reveal that current density concentrates at electrode–propellant contact points and decreases with increasing wire diameter and mesh number, whereas average current density exhibits a non-monotonic trend with mesh number. Thermal stress analysis indicates that pore size affects interfacial stress more significantly than wire diameter, and larger pores increase the risk of debonding. Ignition experiments demonstrate that asymmetric electrode configurations generate current density disparities that override polarity effects in determining the ignition sequence. The influence of electrode material follows the order Ti > SS > Cu and is independent of polarity. Ignition delay increases with propellant thickness, whereas thicknesses below 3 mm are prone to uncontrolled combustion. Under the present electrode configuration and test method, ignition proceeded very slowly at applied voltages below 60 V, whereas ignition occurred readily above 70 V. These findings provide practical guidance for electrode design and operational optimization in electrically controlled solid propulsion systems.