Hybrid Rocket Fill Arm & Cooling System

15%predicted oxidizer capacity increase

Detail view of the vented aluminum shelf inside the insulated cooling shell

CAD assembly of the launch-tower-mounted fill arm and cooling system

Objectives

Develop a launch-tower-mounted system to cool the rocket’s nitrous-oxide tank before and during filling
Increase the temperature and pressure differential between the flight tank and ground supply to store more oxidizer
Integrate cooling and filling equipment that can disconnect and retract safely before launch

Approach

Created a control-volume thermal model incorporating conduction through the insulation and convection through the enclosure, producing an estimated heat-transfer rate of 84.9 W
Designed a two-piece insulated cooling shell with vented aluminum shelves and fan-driven airflow to circulate cold air around the oxidizer tank
Built the supporting structure around hinged aluminum-extrusion frames actuated by double-acting pneumatic cylinders
Integrated the fill line through a pneumatically actuated quick-disconnect mechanism that remains connected during cooling and filling, then retracts with the shell away from the rocket’s launch path
Designed the quick-disconnect interface using a steel mounting plate and custom 3D-printed linkage
Performed FEA on the frame, mounting plate, and printed interface to validate each load-bearing component

Results

Calculated an approximately 37% reduction in nitrous-oxide vapour pressure by reducing the tank temperature from 20°C to 0°C
Predicted an approximately 15% increase in oxidizer capacity without changing the tank volume
Sized the pneumatic actuation system to provide more than twice the estimated force required to open the cooling shell
Achieved a simulated factor of safety above 2 for each analyzed structural component
The rocket has not yet launched; the integrated fill-arm and cooling system is planned to undergo its first launch-environment trial at Launch Canada 2027

Additional Team Contributions

Beyond design work, I contributed to the broader development of the team’s hybrid rocket through hands-on assembly and integration of mechanical components. I also supported the setup, instrumentation, and data collection for the team’s cold-flow and hot-fire tests.