Video: Test of the 3D-printed combustion chamber with a propellant combination of liquid oxygen and methane
The combustion chamber is first precooled by the methane flowing through it. This causes humidity in the air to condense and ice to form on the combustion chamber. The cooling starts in the nozzle throat before proceeding upstream to the injection head. When the combustion chamber is ignited, heat is transferred to the cooling medium and the ice melts and evaporates.