Air blast fuel nozzle system

Claim 2

A recuperated gas turbine engine comprising: (a) a gas operable turbine; (b) a combustor; (c) a compressor drivably connected to said turbine; (d) a recuperative heat exchanger having first and second thermally communicating flow paths extending therethrough; (e) first conduit means for flowing exhaust gas discharged from said combustor through said turbine to operate the same, and then through said first heat exchanger flow path; (f) second conduit means for flowing air discharged from said compressor through said second heat exchanger flow path for recuperation of heat from turbine discharge gas flowing through said first heat exchanger flow path, and for flowing the recuperated compressor discharge air into said combustor; (g) air blast nozzle means mounted on said combustor for receiving and mixing fuel and pressurized air and injecting the fuel-air mixture into said combustor for mixture and combustion with said recuperated air entering said combustor; (h) third conduit means for flowing nonrecuperated compressor discharge air into and through said nozzle means to form and inject said fuel-air mixture, substantially all nonrecuperated compressor discharge air entering said combustor passing through said nozzle means; (i) boost pump means disposed in said third conduit means for selectively and controllably boosting the pressure of said nonrecuperated compressor discharge air entering said nozzle means; and (j) control means for energizing said boost pump means when the pressure level of said nonrecuperated compressor discharge air received by said nozzle means is less than a predetermined magnitude, and for de-energizing said boost pump means when said pressure level exceeds said predetermined magnitude.

Claim 3

A recuperated gas turbine engine comprising: (a) a gas operable turbine; (b) a combustor; (c) a compressor drivably connected to said turbine; (d) a recuperative heat exchanger having first and second thermally communicating flow paths extending therethrough; (e) first conduit means for flowing exhaust gas discharged from said combustor through said turbine to operate the same, and then through said first heat exchanger flow path; (f) second conduit means for flowing air discharged from said compressor through said second heat exchanger flow path for recuperation of heat from turbine discharge gas flowing through said first heat exchanger flow path, and for flowing the recuperated compressor discharge air into said combustor; (g) air blast nozzle means mounted on said combustor for receiving and mixing fuel and pressurized air and injecting the fuel-air mixture into said combustor for mixture and combustion with said recuperated air entering said combustor; (h) third conduit means for flowing nonrecuperated compressor discharge air into and through said nozzle means to form and inject said fuel-air mixture, substantially all nonrecuperated compressor discharge air entering said combustor passing through said nozzle means; (i) boost pump means operably disposed along said third conduit means; (j) a bypass conduit connected to said third conduit means in parallel with said boost pump means; (k) a valve disposed at the upstream juncture of said bypass conduit and said third conduit means for selectively closing one or the other of said bypass conduit and said third conduit means to air flow; and (l) control means, responsive to the pressure level of nonrecuperated compressor discharge air supplied to said nozzle means, for moving said valve to close said bypass conduit when said pressure level is less than a predetermined magnitude, and for moving said valve to close said third conduit means when said pressure level exceeds said predetermined magnitude.

Claim 4

A recuperated gas turbine engine comprising: (a) a gas operable turbine; (b) a combustor; (c) a compressor drivably connected to said turbine; (d) a recuperative heat exchanger having first and second thermally communicating flow paths extending therethrough; (e) first conduit means for flowing exhaust gas discharged from said combustor through said turbine to operate the same, and then through said first heat exchanger flow path; (f) second conduit means for flowing air discharged from said compressor through said second heat exchanger flow path for recuperation of heat from turbine discharge gas flowing through said first heat exchanger flow path, and for flowing the recuperated compressor discharge air into said combustor; (g) air blast nozzle means mounted on said combustor for receiving and mixing fuel and pressurized air and injecting the fuel-air mixture into said combustor for mixture and combustion with said recuperated air entering said combustor; (h) third conduit means for flowing nonrecuperated compressor discharge air into and through said nozzle means to form and inject said fuel-air mixture, substantially all nonrecuperated compressor discharge air entering said combustor passing through said nozzle means; (i) boost pump means operably disposed along said third conduit means; (j) a bypass conduit connected to said third conduit means in parallel with said boost pump means; (k) a valve disposed at the upstream juncture of said bypass conduit and said third conduit means for selectively closing one or the other of said bypass conduit and said third conduit means to air flow; and (l) control means, responsive to the pressure level of nonrecuperated compressor discharge air supplied to said nozzle means, for moving said valve to close said bypass conduit when said pressure level is less than a predetermined magnitude, and for moving said valve to close said third conduit means when said pressure level exceeds said predetermined magnitude.

Claim 5

A recuperated gas turbine engine as recited in claim 1 or 2 wherein said control means include pressure sensing means disposed in said third conduit means between said boost pump means and said air blast nozzle means.

Claim 6

For use with a recuperated gas turbine engine having a turbine, a compressor drivably connected to the turbine, a combustor, a recuperator having first and second thermally communicating passages extending therethrough, and means defining a secondary air flow path for flowing air discharged from the compressor sequentially through the first recuperator passage, the combustor, the turbine, and the second recuperator passage, an air blast fuel nozzle system comprising: (a) a fuel-air mixing air blast nozzle adapted to be operatively mounted on the combustor; (b) primary air flow path means for flowing nonrecuperated compressor discharge air into the combustor in a manner such that substantially all nonrecuperated compressor discharge air entering the combustor passes through said air blast nozzle; (c) an air boost pump operatively mounted along said primary air flow path means; and (d) control means for utilizing said boost pump to maintain a predetermined minimum nozzle air inlet pressure despite variations in compressor discharge pressure, said control means including pressure sensing means disposed in said primary air flow path means between said boost pump and said nozzle.

Claim 7

For use with a recuperated gas turbine engine having a turbine, a compressor drivably connected to the turbine, a combustor, a recuperator having first and second thermally communicating passages extending therethrough, and means defining a secondary air flow path for flowing air discharged from the compressor sequentially through the first recuperator passage, the combustor, the turbine, and the second recuperator passage, an air blast fuel nozzle system comprising: (a) a fuel-air mixing air blast nozzle adapted to be operatively mounted on the combustor; (b) primary air flow path means for flowing nonrecuperated compressor discharge air into the combustor in a manner such that substantially all nonrecuperated compressor discharge air entering the combustor passes through said air blast nozzle; (c) an air boost pump operatively mounted along said primary air flow path means; and (d) control means for utilizing said boost pump to maintain a predetermined minimum nozzle air inlet pressure despite variations in compressor discharge pressure, said control means including pressure sensing means disposed in said primary air flow path means between said boost pump and said nozzle.

Claim 8

An air blast fuel nozzle system as recited in claim 4 wherein said control means further include means interconnected between said pressure sensing means and said boost pump for cycling said boost pump in response to variations in the sensed nozzle air inlet pressure.

Claim 9

An air blast fuel nozzle system as recited in claim 4 wherein said control means further include a bypass conduit connected to said primary air flow path means in parallel with said boost pump, valve means disposed at the upstream juncture of said bypass conduit and said primary air flow path means and selectively operable to close one or the other of said bypass conduit and said primary air flow path means to air flow, and means interconnected between said pressure sensing means and said valve means for operating said valve means in response to variations in the sensed nozzle air inlet pressure.