# US 11,028,803 B2 · Resin transfer molded rocket motor nozzle with adaptive geometry > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,028,803 B2 - Document ID: US11028803B2 - Status: Granted - Kind: B2 - Application number: 16/126,225 - Filed: 2018-09-10 - Published: 2020-03-12 - Granted: 2021-06-08 - Earliest claimed: 2018-09-10 - Assignees: Raytheon Company - Applicants: Raytheon Company - Inventors: Matt H. Summers; David M. Case; John J. Raymond, IV; Gray Fowler; Mark T. Langhenry - Web page: https://patentgrep.com/patent/US11028803B2 ## CPC - F02K 9/974: {Nozzle- linings; Ablative coatings} - F02K 9/86: using nozzle throats of adjustable cross- section {(F02K9/978 takes precedence)} - B29C 70/44: using isostatic pressure, e.g. pressure difference-moulding, vacuum bag-moulding, autoclave-moulding or expanding rubber-moulding - F05D 2230/31: Layer deposition - F05D 2300/44: Resins - F05D 2300/506: Hardness - 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) - B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00) - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS ## Abstract A rocket motor has a nozzle that is reconfigurable by erosion or ablation of the material around the throat of the nozzle. The nozzle throat has layers of materials with different erosion characteristics, with the erosion occurring so as to achieve the desired nozzle characteristics (configurations) during different parts of the fuel burn. The nozzle throat includes relatively-high-erosion material layers and relatively-low-erosion material layers, with some layers of the throat resisting erosion, while other of the layers erode or ablate relatively quickly. The relatively-low-erosion material layers may act as thermal barriers to fix the throat at relatively stable geometry for long periods of time, such as during most of the burn of different fuel segments, with the relatively-high-erosion material layers allowing rapid transition of the throat from one geometry to the next. The layers may be made by resin transfer molding (RTM). ## Claims ### Claim 1 A rocket motor nozzle comprising: a pair of relatively-low-erosion material layers; and a relatively-high-erosion material layer sandwiched between the relatively-low-erosion material layers; wherein each of the pair of relatively-low-erosion material layers and the relatively-high-erosion material layer include resin-transfer molded materials; wherein the resin transfer molded material of the pair of relatively-low-erosion material layers and the resin transfer molded material of the relatively-high-erosion material layer are different materials; wherein the relatively-high-erosion material layer k made of a relatively-high-erosion material that erodes more quickly when exposed to flow through the nozzle than does a relatively-low-erosion material or materials of the relatively-low-erosion material layers; and wherein the relatively-low-erosion material layers include: an inner relatively-low-erosion material layer that radially inwardly overlaps the relatively-high-erosion material layer; and an outer relatively-low-erosion material layer that radially outwardly overlaps the relatively-high-erosion material layer. ### Claim 2 (depends on 1) The rocket motor nozzle of claim 1, wherein the relatively-low-erosion material or materials includes fibers; and wherein the relatively-high-erosion material is fiberless. ### Claim 3 (depends on 1) The rocket motor nozzle of claim 1, wherein the relatively-low-erosion material or materials includes fibers; and wherein the relatively-high-erosion material includes fibers of a different material than the fibers of the relatively-low-erosion material or materials. ### Claim 4 (depends on 1) The rocket motor nozzle of claim 1, wherein the relatively-low-erosion material layers include the same material. ### Claim 5 (depends on 1) The rocket motor nozzle of claim 1, wherein the relatively-high-erosion material layer is an inner relatively-high-erosion material layer; and further comprising an outer relatively-high-erosion material layer that is radially outward of the inner relatively-high-erosion material layer, and is radially outward of the relatively-low-erosion material layers. ### Claim 6 (depends on 1) The rocket motor nozzle of claim 1, in combination with fuel, as a part of a rocket motor. ### Claim 7 (depends on 6) The combination of claim 6, wherein the fuel is a solid fuel. ### Claim 8 (depends on 7) The combination of claim 7, wherein the solid fuel is in multiple segments. ### Claim 9 (depends on 6) The combination of claim 6, wherein the motor is configured to burn the fuel in multiple pulses; and wherein the nozzle is configured such that during most of a first pulse of the multiple pulses the inner relatively-low-erosion material layer defines a channel of the nozzle through which combustion gasses pass, and such that during most of a second pulse of the multiple pulses the outer relatively-low-erosion material layer defines the channel of the nozzle. ### Claim 10 A rocket motor comprising: a first fuel portion; a second fuel portion; and a nozzle operatively coupled to the fuel portions, with hot gasses produced by burning of the fuel portions passing through the nozzle; wherein the nozzle includes: a pair of relatively-low-erosion material layers; and a relatively-high-erosion material layer sandwiched between the relatively-low-erosion material layers; wherein each of the pair of relatively-low-erosion material layers and the relatively-high-erosion material layer include resin-transfer molded materials; wherein the resin transfer molded material of the pair of relatively-low-erosion material layers and the resin transfer molded material of the relatively-high-erosion material layer are different materials; wherein the relatively-high-erosion material layer is made of a material that erodes more quickly when exposed to flow through the nozzle than does a material or materials of the relatively-low-erosion material layers; and wherein the relatively-low-erosion material layers include: an inner relatively-low-erosion material layer that radially inwardly overlaps the relatively-high-erosion material layer; and an outer relatively-low-erosion material layer that radially outwardly overlaps the relatively-high-erosion material layer. ### Claim 11 (depends on 10) The rocket motor of claim 10, wherein the fuel portions are parts of a single solid fuel segment. ### Claim 12 (depends on 10) The rocket motor of claim 10, wherein the portions are separate fuel segments, with the first fuel portion being a first fuel segment and the second fuel portion being a second fuel segment; and wherein the first fuel segment and the second fuel segment are configured to be burned sequentially, with the first fuel segment burned before the second fuel segment. ### Claim 13 (depends on 12) The rocket motor of claim 12, wherein there is no non-fuel-burning time between the burning of the first fuel segment and the burning of the second fuel segment. ### Claim 14 (depends on 10) The rocket motor of claim 10, wherein the nozzle is configured such that during most of burning of the first fuel portion the inner relatively-low-erosion material layer defines a channel of the nozzle through which combustion gasses pass, and such that most of burning of the second fuel portion of the multiple pulses the outer relatively-low-erosion material layer defines the channel of the nozzle. ### Claim 15 A method of operating a rocket motor, the method comprising: burning a first portion of fuel of the motor, with a nozzle of the motor in a first configuration, with a channel in the nozzle defined by an inner relatively-low-erosion material layer of the nozzle, with the inner relatively-low-erosion material layer eroding during the burning of the first portion; after the burning of at least most of the first portion, and after the inner relatively-low-erosion material layer eroding to expose a relatively-high-erosion material layer that initially underlies the inner relatively-low-erosion material layer, transforming the nozzle from the first configuration to a second configuration by eroding the relatively-high-erosion material layer to expose an outer relatively-low-erosion material layer that initially underlies the relatively-high-erosion material layer; and after the transforming, burning a second portion of the fuel, with the nozzle in the second configuration; wherein each of the inner relatively-low-erosion material layer, the relatively-high-erosion material layer and the outer relatively-low-erosion material layer include resin-transfer molded materials; wherein the resin transfer molded material of the pair of relatively-low-erosion material layers and the resin transfer molded material of the relatively-high-erosion material layer are different materials. ### Claim 16 (depends on 15) The method of claim 15, wherein the burning of the second fuel portion follows immediately continuously the burning of the first fuel portion. ### Claim 17 (depends on 15) The method of claim 15, wherein the eroding the relatively-high-erosion material layer to expose the outer relatively-low-erosion material layer occurs at least in part during the burning of the first portion. ### Claim 18 (depends on 15) The method of claim 15, wherein the eroding the relatively-high-erosion material layer to expose the outer relatively-low-erosion material layer occurs at least in part during the burning of the second portion. ### Claim 19 (depends on 15) The method of claim 15, wherein the burning of the first portion produces a different thrust than the burning of the second portion.