The potential for overheating either the faceplate or the body of a device injecting liquid oxygen (LOX) into a duct in which hydrogen is flowing at high temperature (2,850K) is extremely high. The temperature of the hydrogen alone (i.e., without combustion) is above the melting point of many materials, so adding to that the additional heat flux of a closely-anchored diffusion flame zone is an extremely difficult design challenge. Rigimesh is a tried and true transpiration cooling technology that has been used in the manufacture of injector faceplates used in a number of high power liquid rocket engines, including the J-2, RL-10 and Space Shuttle Main Engine.
Our innovation, which we will prove to be feasible in Phase I, is an imbedded, single-piece LOX injector manufactured exclusively using selective laser melting (SLM), a modern additive manufacturing (AM, also known as 3D printing) technique. Using an AM approach provides the ability to infinitely tailor the transpiration cooling (optimizing to local conditions) at significantly reduced cost and manufacturing lead time over state of the art Rigimesh. And because SLM is proven to be capable of printing extremely complex components (more below), the injector is not restricted to simple, flat geometries. The designer is absolutely free to use any geometry to simultaneously provide the required injection performance within the constraints of the given duct geometry.
Exploration Upper Stage Engine
Planetary Lander and Ascent Vehicle Main Engines