# US 12,109,445 B2 · Fire extinguishing system and method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,109,445 B2 - Document ID: US12109445B2 - Status: Granted - Kind: B2 - Application number: 17/806,910 - Filed: 2022-06-14 - Published: 2023-12-14 - Granted: 2024-10-08 - Earliest claimed: 2022-06-14 - Assignees: The Boeing Company - Applicants: The Boeing Company - Inventors: John A. Weidler; George A. McEachen; Robert S. Wright; Daniel W. Baisley; Sarah M. Wickham; Mark D. Byers - Web page: https://patentgrep.com/patent/US12109445B2 ## CPC - A62C 31/005: {using nozzles} - A62C 3/08: in aircraft {(A62C3/0207 takes precedence)} - A62C 35/023: {the extinguishing material being expelled by compressed gas, taken from storage tanks, or by generating a pressure gas (for foam generation A62C5/02)} - A62C 35/13: with a finite supply of extinguishing material - A62C 35/68: Details, e.g. of pipes or valve systems (valves in general F16K) - B64D 45/00: Aircraft indicators or protectors not otherwise provided for - B64D 2045/009: {Fire detection or protection; Erosion protection, e.g. from airborne particles} - A62C: FIRE-FIGHTING (fire-extinguishing compositions, use of chemical substances in extinguishing fires A62D1/00; spraying, applying liquids or other fluent materials to surfaces in general B05; alarm arrangements G08B, e.g. fire alarms actuated by smoke or gases G08B17/10) - B64D: EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT ## Abstract A fire extinguishing system includes a storage vessel and a fluidic oscillator. The storage vessel is configured to contain a fire extinguishing agent. The fluidic oscillator is configured to receive the fire extinguishing agent from the storage vessel, and discharge a continuous jet of the fire extinguishing agent while oscillating the jet back and forth through a sweep angle. ## Claims ### Claim 1 An aircraft, comprising: a turbofan engine having: a fan duct outer wall surrounding rotatable fan blades and configured to receive an air flow; a fan duct inner wall surrounding an engine core located downstream of the fan blades, the fan duct inner wall and the engine core defining an annular gap configured to receive a core flow as a portion of the air flow; a storage vessel configured to contain a fire extinguishing agent in a liquid form; and a fluidic oscillator configured to receive the fire extinguishing agent from the storage vessel, and discharge a continuous jet of the fire extinguishing agent into the core flow passing through the annular gap while oscillating the jet back and forth through a sweep angle. ### Claim 2 (depends on 1) The aircraft of claim 1, further comprising: an agent transfer tube fluidically coupling the storage vessel to the fluidic oscillator. ### Claim 3 (depends on 1) The aircraft of claim 1, wherein: the fluidic oscillator is configured to oscillate the jet through the sweep angle in the range of 30-120 degrees. ### Claim 4 (depends on 1) The aircraft of claim 1, wherein: the fluidic oscillator is configured to oscillate the jet at an oscillating frequency in the range of 5-20 Hz. ### Claim 5 (depends on 1) The aircraft of claim 1, wherein: the fluidic oscillator is configured to discharge the jet in a manner causing the jet to break up into droplets having a droplet size of less than 150 microns. ### Claim 6 (depends on 1) The aircraft of claim 1, wherein the fluidic oscillator is mounted above the engine core, and is configured such that the jet distributes the fire extinguishing agent alternately on opposite sides of the engine core. ### Claim 7 (depends on 1) The aircraft of claim 1, wherein the fluidic oscillator comprises: a main body having a power nozzle and an exit throat; an internal cavity containing a pair of flow separators separating a mixing region respectively from a pair of feedback channels, each of the feedback channels has a channel entrance at the exit throat, and a channel exit at the power nozzle; the power nozzle is configured to receive the fire extinguishing agent from the storage vessel, and direct a main flow of the fire extinguishing agent into the mixing region; and each flow separator is configured to alternately cause a portion of the main flow to enter the channel entrance of the feedback channel defined by the flow separator, and exit the feedback channel at the power nozzle in a manner generating a separation vortex that pushes the main flow across the mixing region and toward the flow separator on an opposite side of the mixing region, causing the jet to change direction across the sweep angle. ### Claim 8 (depends on 7) The aircraft of claim 7, wherein: the main body terminates at the exit throat where the jet is discharged. ### Claim 9 (depends on 7) The aircraft of claim 7, wherein: the fluidic oscillator is symmetrical about a central axis centered on the power nozzle and the exit throat. ### Claim 10 (depends on 1) The aircraft of claim 1, wherein: the storage vessel contains one of the following compounds as the fire extinguishing agent: trifluoroiodomethane, fluoroketone, pentafluoroethane, or bromotrifluoromethane. ### Claim 11 (depends on 1) A method of extinguishing a fire, the method comprising: providing the aircraft of claim 1; storing fire extinguishing agent in the storage vessel; receiving, from the storage vessel, the fire extinguishing agent at the fluidic oscillator; and discharging the continuous jet of the fire extinguishing agent from the fluidic oscillator into the core flow while oscillating the jet back and forth through the sweep angle. ### Claim 12 (depends on 11) The method of claim 11, wherein discharging the jet comprises: oscillating the jet through the sweep angle in the range of 30-120 degrees. ### Claim 13 (depends on 11) The method of claim 11, wherein discharging the jet comprises: oscillating the jet at an oscillating frequency in the range of 5-20 Hz. ### Claim 14 (depends on 11) The method of claim 11, wherein discharging the jet comprises: discharging the jet in a manner causing the jet to break up into droplets having a droplet size in the range of less than 150 microns. ### Claim 15 (depends on 11) The method of claim 11, wherein discharging the jet comprises: discharging one of the following compounds as the fire extinguishing agent: trifluoroiodomethane, fluoroketone, pentafluoroethane, or bromotrifluoromethane. ### Claim 16 (depends on 11) The method of claim 11, wherein the aircraft further comprises an agent transfer tube fluidically coupling the storage vessel to the fluidic oscillator. ### Claim 17 (depends on 11) The method of claim 11, wherein the fluidic oscillator is mounted above the engine core, and is configured such that the jet distributes the fire extinguishing agent alternately on opposite sides of the engine core. ### Claim 18 (depends on 11) The method of claim 11, wherein the fluidic oscillator comprises: a main body having a power nozzle and an exit throat; an internal cavity containing a pair of flow separators separating a mixing region respectively from a pair of feedback channels, each of the feedback channels has a channel entrance at the exit throat, and a channel exit at the power nozzle; the power nozzle is configured to receive the fire extinguishing agent from the storage vessel, and direct a main flow of the fire extinguishing agent into the mixing region; and each flow separator is configured to alternately cause a portion of the main flow to enter the channel entrance of the feedback channel defined by the flow separator, and exit the feedback channel at the power nozzle in a manner generating a separation vortex that pushes the main flow across the mixing region and toward the flow separator on an opposite side of the mixing region, causing the jet to change direction across the sweep angle. ### Claim 19 (depends on 18) The method of claim 18, wherein: the main body terminates at the exit throat where the jet is discharged. ### Claim 20 (depends on 18) The method of claim 18, wherein: the fluidic oscillator is symmetrical about a central axis centered on the power nozzle and the exit throat.