Patent Application
20080016846
The various features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the currently preferred embodiment. The drawings that accompany the detailed description can be briefly described as follows:
A combustion chamber wall 20 about a thrust axis A defines the nozzle assembly 12. The combustion chamber wall 20 defines a thrust chamber 22, a combustion chamber 24 upstream of the thrust chamber 22, and a combustion chamber throat 26 therebetween. The nozzle assembly 12 includes an injector face 28 with a multitude of fuel/oxidizer injector elements 30 (shown schematically) which receive fuel which passes first through the fuel cooled combustion chamber wall 20 fed via fuel supply line 14a of the fuel system 14 and an oxidizer such as Gaseous Oxygen (GOx) through an oxidizer supply line 16a of the oxidizer system 16.
Heat in the fuel cooled combustion chamber wall 20 serves to superheat and/or at least partially vaporize the fuel. The fuel vapor is then passed through a turbine 32 and injected into the combustion chamber 24 to burn with the oxidizer as generally understood. Preferably, all the propellants are burned at the optimal mixture ratio in the combustion chamber 24, and typically no flow is dumped overboard; however, heat transfer to the fuel is typically the limiting factor of the power available to the turbine 32.
Referring to
As the fuel passes through the deoxygenator system 34, oxygen is selectively removed into a vacuum or sweep-gas system 36. The sweep gas may be any gas that is essentially free of oxygen. The deoxygenated fuel flows from a fuel outlet of the deoxygenation system 34 via a deoxygenated fuel conduit, to the fuel cooled combustion chamber wall 20. It should be understood that although a particular component arrangement is disclosed in the illustrated embodiment, other arrangements will benefit from the instant invention.
Referring to
The oxygen permeable membrane 40 allows dissolved oxygen (and other gases) to diffuse through angstrom-size voids but excludes the larger fuel molecules. Alternatively, or in conjunction with the voids, the oxygen permeable membrane 40 utilizes a solution-diffusion mechanism to dissolve and diffuse oxygen (and/or other gases) through the membrane while excluding the fuel. The family of Teflon AF which is an amorphous copolymer of perfluoro-2,2-dimethyl-1,3-dioxole (PDD) often identified under the trademark “Teflon AF” registered to E. I. DuPont de Nemours of Wilmington, Del., USA, and the family of Hyflon AD which is a copolymer of 2,2,4-trifluoro-5-trifluoromethoxy-1,3-dioxole (TDD) registered to Solvay Solexis, Milan, Italy have proven to provide effective results for fuel deoxygenation.
Fuel flowing through the fuel channel 44 is in contact with the oxygen permeable membrane 40. Vacuum creates an oxygen partial pressure differential between the inner walls of the fuel channel 44 and the oxygen permeable membrane 40 which causes diffusion of oxygen dissolved within the fuel to migrate through the porous support 46 which supports the membrane 40 and out of the deoxygenator system 34 through the oxygen receiving channel 42.
The specific quantity of assemblies 38 are determined by application-specific requirements, such as fuel type, fuel temperature, and mass flow demand from the engine. Further, different fuels containing differing amounts of dissolved oxygen may require differing amounts of deoxygenation to remove a desired amount of dissolved oxygen. For further understanding of other aspects of one membrane based fuel deoxygenator system and associated components thereof which are capable of processing high flow rates characteristic of rocket engines in a compact and lightweight assembly, and lowering dissolved oxygen concentration sufficiently to suppress coke formation, attention is directed to U.S. Pat. No. 6,315,815 entitled MEMBRANE BASED FUEL DEOXYGENATOR; U.S. Pat. No. 6,939,392 entitled SYSTEM AND METHOD FOR THERMAL MANAGEMENT and U.S. Pat. No. 6,709,492 entitled PLANAR MEMBRANE DEOXYGENATOR which are assigned to the assignee of the instant invention and which are hereby incorporated herein in their entirety.
It should be understood that relative positional terms such as “forward,” “aft,” “upper,” “lower,” “above,” “below,” and the like are with reference to the normal operational attitude of the vehicle and should not be considered otherwise limiting.
It should be understood that although a particular component arrangement is disclosed in the illustrated embodiment, other arrangements will benefit from the instant invention.
For further understanding of other aspects of the airflow distribution networks and associated components thereof, attention is directed to U.S. Pat. No. 5,327,744 which is assigned to the assignee of the instant invention and which is hereby incorporated herein in its entirety.
Although particular step sequences are shown, described, and claimed, it should be understood that steps may be performed in any order, separated or combined unless otherwise indicated and will still benefit from the present invention.
The foregoing description is exemplary rather than defined by the limitations within. Many modifications and variations of the present invention are possible in light of the above teachings. The preferred embodiments of this invention have been disclosed, however, one of ordinary skill in the art would recognize that certain modifications would come within the scope of this invention. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. For that reason the following claims should be studied to determine the true scope and content of this invention.
