Design

Engine Diagram

Valve Stack

This is the ground of valves, fittings, and connectors that make up what is know as the "valve stack". This separates the oxidizer tank and combustion chamber that controls the fluid fill, pressurization, and injection.

Injector

This steel component has orifices designed to inject and atomize the liquid oxidizer over the solid fuel to facilitate combustion. This component is critical as it controls the oxidizer flow, and determines the mass flow rate of oxidizer by modulating the orifice size. This component is made out of steel as it is exposed to massive thermal flux, and protects the rest of the engine component from the combustion chamber temperatures.

Combustion Chamber

This is chamber makes up the bulk structure of the engine. This component houses the oxidizer-fuel combustion reaction that produces thrust. The walls are protected with a phenolic liner, which the fuel grain is cast into. This phenolic is a fiberglass-like material that ablates as the engine burns and carries the thermal energy out of the nozzle and away from the engine.

Nozzle

This component is how we control the flow from the combustion chamber to ambient air. It is known as a sonic nozzle, as the flow is converged, then diverged such that the flow at the throat is exactly mach 1, this ensure efficient expansion of the flow, maximizing engine thrust. This component is made out of graphite, making it extremely brittle and fragile, causing manufacturing and assembly to be difficult. It is essential to use graphite as the material due to graphite's thermal properties, graphite does very well in high heat conditions making it an ideal candidate for nozzle construction.

Solid Fuel

Custom solid fuel, dubbed 'Supersand,' was formulated for the HADES hybrid engine. It consists of 20% HTPB, 70% aluminum powder, and 10% currants, devoid of any oxidizer. Consequently, the fuel remains inert, necessitating an external oxidizer source for ignition. This characteristic renders the fuel exceptionally safe, requiring no additional safety measures during handling. The inclusion of aluminum powder enhances mass expulsion during engine operation, thereby improving peak thrust performance and increasing the likelihood of successful liftoff for the vehicle.