Development and validation of heat resistant rolling and deformation absorbing nozzle necks for friction and reaction force reduction

Minimizing frictional forces due to jamming between critical components such as shutters and nozzle necks is essential for ensuring the reliability of solid-propellant thrusters. This study presents innovative Rod-type and Slot-pin nozzle neck designs, incorporating rolling-structure concepts and high-temperature-resistant materials to effectively reduce friction in extreme operational conditions. The Slot-pin design, in particular, integrates a deformation-absorbing mechanism that accommodates initial interference, further mitigating frictional forces. Experimental results demonstrate that both designs significantly decrease friction compared to conventional configurations, with the Slot-pin design achieving superior performance at low interference distances. Finite Element Method (FEM) structural analyses corroborate these findings, highlighting each design's capacity to prevent jamming-induced mechanical failures. This research provides critical insights into friction reduction and deformation-absorbing strategies for high-stress aerospace components, establishing a robust framework for enhanced durability and performance.