NOS/Ethanol Program
The Case Liquid Propulsion Team is currently developing a nitrous oxide and ethanol liquid rocket engine designed to produce approximately 425 lbf of thrust. The project represents the team’s first complete liquid propulsion system and combines engine development, ground support equipment, fluid systems, structural design, manufacturing, avionics, and testing into a single integrated platform.
Engine Development
The engine architecture has progressed from initial performance calculations into detailed component design and manufacturing. The current design uses nitrous oxide as the oxidizer and ethanol as the fuel, with a coaxial injector delivering the propellants to the combustion chamber. The engine is designed around a chamber pressure of approximately 500 psi, with targeted oxidizer and fuel mass flow rates of approximately 0.669 kg/s and 0.243 kg/s, respectively.
Significant work has also been completed on the engine’s regenerative cooling system. Ethanol is routed through cooling passages surrounding the combustion chamber before entering the injector, allowing the fuel to absorb heat from the chamber walls while improving the thermal survivability of the engine. Injector, chamber, manifold, and cooling designs are continuing to be refined through analytical modeling, simulation, manufacturing studies, and subsystem testing.
Ground Support & Fluid Systems
The ground support equipment (GSE) is being developed alongside the engine to safely store, pressurize, control, and deliver both propellants during testing. Separate nitrous oxide and ethanol tanks are top-pressurized with nitrogen, with the feed system designed to maintain the pressure required to achieve the engine’s target mass flow rates throughout the burn.
The team has developed and iterated a complete Piping and Instrumentation Diagram (P&ID) defining the propellant, pressurization, vent, fill, and control systems. Current work includes pressure-drop modeling, valve and regulator selection, tubing and fitting design, propellant tank manufacturing, and characterization of flow restrictions through the feed system and injector. These models are being used to predict operating pressures throughout the system and ensure that the fuel and oxidizer arrive at the injector at the required conditions.
A dedicated test stand is also being manufactured to support hydrostatic testing, cold-flow testing, and eventual hot-fire operations. The stand incorporates remotely controlled valves, pressure instrumentation, structural mounting systems, and a thrust measurement assembly designed to directly measure engine performance.
Avionics & Data Acquisition
The avionics system provides the control and instrumentation necessary to safely operate and characterize the engine. Pressure transducers, thermocouples, and a load cell will be used to measure propellant pressures, temperatures, and engine thrust throughout each test.
The system is being developed around remote operation and automated data acquisition, allowing the team to control valves and monitor critical parameters from a safe distance during testing. Avionics development is being closely integrated with the fluid system so that sensors and control hardware correspond directly to important locations throughout the P&ID.
Moving Toward Hot Fire
With the overall engine architecture established, the project is transitioning increasingly from design into manufacturing, integration, and subsystem validation. Components of the engine, propellant tanks, test stand, fluid system, and avionics are being manufactured and assembled while the team conducts structural, hydrostatic, and flow testing.
These efforts will ultimately converge in an integrated cold-flow campaign followed by the team’s first liquid-engine hot-fire test. Each subsystem is being designed not only to support this engine, but also to establish the infrastructure, procedures, and technical knowledge needed for future liquid propulsion development at Case Western Reserve University.