Rotating Detonation Engine Novel Injector Design

Astrobotic will design, manufacture, and test a series of flight-like rotating detonation rocket engine (RDRE) injectors using its patent-pending PermiAM technology. In addition to the further development and test of these injectors, Astrobotic will also design an annular RDRE chamber that will be compatible with the injectors. The proposed innovation is a flight-like rotating detonation rocket engine (RDRE) injector using Astrobotic’s patent-pending permeable additive manufacturing (PermiAM) method. This injector will provide improved propellant distribution and cooling compared to traditional injector designs, allowing for a stable detonation wave. This design will bring RDREs one step closer to being a practical choice over traditional liquid rocket engines, and the additive manufacturing process allows Astrobotic to reduce the cost of injector builds by up to 60%. There has recently been a push to take RDRE designs and give them more flight-like configurations. RDREs also need effective cooling methods, and PermiAM has demonstrated it can withstand the high temperature and pressure environment of a rocket engine while keeping the injector face temperature cool. CFD analysis performed during Phase I indicates that a PermiAM injector can provide the necessary pressure differential and propellant flow required for an RDRE. Technical Objectives Design: Building off the data acquired during Phase I testing, Astrobotic will develop a new series of PermiaAM RDRE injectors that explore different propellant mixing geometries. Manufacture: The injector and chamber designs will be sent to an additive manufacturer to be 3D printed. Astrobotic will then receive the prints to inspect and verify the quality of the parts. Test: Planning for testing will begin in parallel with the manufacturing phase. Each injector will undergo cold-flow and hot-fire testing. Proposed Deliverables Design: Preliminary Design Review; Detailed Design Review Manufacturing: Manufacturing Readiness Review Test: Test Readiness Review; Final Report
Benefits: Injectors manufactured using PermiAM provide numerous benefits to NASA, including PermiAM's ability to evenly inject propellants across the detonation wave path, which helps to maintain the stability of the detonation wave in an RDRE. These injectors and compatible thrust chambers may be able to improve Isp by as much as 15%. Such RDREs could be used on spacecraft or launch vehicles for NASA missions and may be useful for developing new space and aviation propulsion systems. Customers for the injectors proposed for this effort include commercial companies working to develop functional RDREs or seeking to improve the efficiency of their propulsion systems. The injectors, as part of a functional RDRE, could be sold as an efficient commercial propulsion system to private spacecraft and launch providers. RDRE technology is also a key research area for the Air Force.