The study of convergent-divergent nozzle geometry for CubeSat chemical propulsion system

Abstract The satellite was designed to simulate an orbit around a planet, serving as a vital tool for space exploration. To reduce resource consumption and development time, nanosatellites, or CubeSats, were developed. Despite their advantages, CubeSats face significant space constraints, often limiting them to payload purposes. However, for certain missions, orbital or directional control becomes essential. To address this, CubeSats incorporate a propulsion system, with the nozzle serving as a critical component. The nozzle converts the high temperature and pressure generated by the propulsion reactor into velocity, enabling precise satellite movement and control. To evaluate the performance of the nozzle, experimental setups and CFD (Computational Fluid Dynamics) simulations were employed. Experimentation involved hydrogen peroxide (H 2 O 2 ) reacting with a silver catalyst under atmospheric pressure. Results demonstrated that increasing the H 2 O 2 flow rate resulted in higher temperatures and pressures. However, a limitation was observed in the silver catalyst, which degraded after initial use, impacting performance. CFD simulations investigated the effects of varying the convergent and divergent half-angles of the nozzle. Findings revealed that the divergent half-angle significantly influenced thrust performance, with an optimal angle of 35 degrees producing maximum thrust due to reduced boundary layer effects. Beyond this angle, thrust efficiency declined. Meanwhile, variations in the convergent half-angle showed minimal impact on thrust generation, highlighting the divergent half-angle’s critical role in optimizing propulsion. These results emphasize the importance of nozzle geometry in CubeSat propulsion systems. By optimizing the divergent half-angle, CubeSats can achieve higher thrust efficiency, enhancing their operational capabilities. The study provides valuable insights for improving the design and performance of CubeSat propulsion systems, enabling more effective satellite manoeuvrability and expanding CubeSat applications in space exploration.