End-Face Ignition Mechanisms in LP-Based ECSP: Combustion Control via On/Off Current Switching

Electronically controlled solid propellant (ECSP) represents a novel approach for achieving variable thrust control in propulsion systems. This propellant type enables regulation of the burn rate and engine ignition/termination solely through voltage modulation, eliminating the requirement for complex structural designs or high-power inputs. In this study, a novel ECSP formulation, utilizing carboxyl-terminated polybutadiene-epoxy resin (CTPB) as the binder matrix, was synthesized and investigated. The ignition characteristics of the ECSP were examined using an electronically controlled combustion test system. Experimental results indicate that increasing the lead perchlorate (LP) content enhances the combustion reaction intensity; however, excessively high LP content adversely affects the propellant’s extinguishment capability. Physical and chemical alterations of the propellant pre- and post-combustion were characterized employing techniques including SEM, XRD, and TG-DSC analysis. Furthermore, the evolution of the thermoelectric field during propellant ignition was simulated using COMSOL Multiphysics software. This facilitated the analysis of physicochemical processes occurring during ECSP ignition, leading to the establishment of an energized ignition and combustion model for the propellant.