# US 8,230,673 B2 · Rocket engine injectorhead with flashback barrier > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,230,673 B2 - Document ID: US8230673B2 - Status: Granted - Kind: B2 - Application number: 12/613,188 - Filed: 2009-11-05 - Published: 2010-11-04 - Granted: 2012-07-31 - Earliest claimed: 2006-12-04 - Assignees: Firestar Engineering, LLC - Inventors: Gregory S. Mungas; David J. Fisher; Christopher Mungas - Web page: https://patentgrep.com/patent/US8230673B2 ## CPC - F02K 9/52: Injectors - F02K 9/94: Re-ignitable or restartable rocket- engine plants; Intermittently operated rocket-engine plants - F02K 9/95: characterised by starting or ignition means or arrangements (safety devices F02K9/38) - F02K: JET-PROPULSION PLANTS (features of jet-propulsion plants common to gas-turbine plants, air intakes or fuel supply control of air-breathing jet-propulsion plants F02C7/00, F02C9/00) ## Abstract Propellants flow through specialized mechanical hardware that is designed for effective and safe ignition and sustained combustion of the propellants. By integrating a micro-fluidic porous media element between a propellant feed source and the combustion chamber, an effective and reliable propellant injector head may be implemented that is capable of withstanding transient combustion and detonation waves that commonly occur during an ignition event. The micro-fluidic porous media element is of specified porosity or porosity gradient selected to be appropriate for a given propellant. Additionally the propellant injector head design integrates a spark ignition mechanism that withstands extremely hot running conditions without noticeable spark mechanism degradation. ## Claims ### Claim 1 A combustion system comprising: a housing defining a chamber having distal and proximal ends; the housing defining a cooling chamber at the proximal end, a combustion chamber at the distal end and a flame barrier between the cooling chamber and the combustion chamber; an electrode assembly disposed through the proximal end of the housing through the cooling chamber and through the flame barrier terminating at a surface of the flame barrier adjacent the combustion chamber, wherein the electrode assembly comprises an electrode disposed within an insulating tube, and wherein the insulating tube is disposed within an interface sheath; and a fuel inlet tube disposed through a side of the housing into the cooling chamber, wherein the flame barrier comprises fluid paths having a diameter of less than about 0.1 micron, wherein the fluid paths are adapted to prevent combustion from propagating through the flame barrier. ### Claim 2 (depends on 1) The combustion system of claim 1 wherein the flame barrier comprises fluid paths having a diameter of less than about 0.05 micron. ### Claim 3 (depends on 2) The combustion system of claim 2 wherein the flame barrier comprises fluid paths having a diameter of less than about 0.02 micron. ### Claim 4 A combustion system comprising: a housing defining a chamber having distal and proximal ends; the housing defining a cooling chamber at the proximal end, a combustion chamber at the distal end and a flame barrier between the cooling chamber and the combustion chamber; an electrode assembly disposed through the proximal end of the housing through the cooling chamber and through the flame barrier terminating at a surface of the flame barrier adjacent the combustion chamber, wherein the electrode assembly comprises an electrode disposed within an insulating tube, and wherein the insulating tube is disposed within an interface sheath; and a fuel inlet tube disposed through a side of the housing into the cooling chamber, wherein the flame barrier comprises fluid paths having a diameter of less than about 500 microns, wherein the fluid paths are adapted to prevent combustion from propagating through the flame barrier. ### Claim 5 (depends on 4) The combustion system of claim 4 wherein the flame barrier comprises fluid paths having a diameter of less than about 200 microns. ### Claim 6 (depends on 5) The combustion system of claim 5 wherein the flame barrier comprises fluid paths having a diameter of less than about 100 microns. ### Claim 7 (depends on 6) The combustion system of claim 6 wherein the flame barrier comprises fluid paths having a diameter of less than about 50 microns. ### Claim 8 (depends on 7) The combustion system of claim 7 wherein the flame barrier comprises fluid paths having a diameter of less than about 20 microns. ### Claim 9 (depends on 8) The combustion system of claim 8 wherein the flame barrier comprises fluid paths having a diameter of less than about 10 microns. ### Claim 10 (depends on 9) The combustion system of claim 9 wherein the flame barrier comprises fluid paths having a diameter of less than about 5 microns. ### Claim 11 (depends on 10) The combustion system of claim 10 wherein the flame barrier comprises fluid paths having a diameter of less than about 2 micron. ### Claim 12 (depends on 1) The combustion system of claim 1, wherein the cooling chamber is adapted to cool the electrode assembly. ### Claim 13 (depends on 4) The combustion system of claim 4, wherein the cooling chamber is adapted to cool the electrode assembly.