Jet engine and method of operating the same

A jet engine comprising:

• a. a housing having an upstream inlet end to receive intake air, a downstream exhaust end to discharge jet exhaust, and an outer side surface exposed directly to free stream air flow,
• b. an air inlet arranged to receive intake air,
• c. a compressor mounted in said housing downstream of said inlet and arranged to compress air flowing into said inlet,
• d. means defining a combustion chamber downstream of said compressor to receive compressed air therefrom and burn fuel in said compressed air to provide a gaseous flow from said combustion chamber,
• e. a turbine section comprising:
• 1. an outer annular wall means,
• 2. an inner annular wall means spaced radially inwardly from said outer annular wall means,
• 3. an intermediate annular wall means positioned between said inner and outer annular wall means,
• 4. forward portions of said outer and inner annular wall means defining a first generally annular passageway downstream of said combustion chamber to receive gaseous flow from said combustion chamber,
• 5. a rear portion of said inner annular wall means and said intermediate annular wall means defining a second inner annular passageway,
• 6. a rear portion of said outer annular wall means and said intermediate wall means defining a third annular passageway positioned radially outwardly of said second passageway,
• 7. a turbine first stage positioned in said first passageway and arranged to receive the gaseous flow from said combustion chamber so as to be driven thereby, with said gaseous flow proceeding to said second and third passageways,
• 8. said intermediate wall means separating the gaseous flow into first and second portions, with said first portion travelling through said second passageway, and said second portion travelling through said third passageway,
• 9. a turbine second stage positioned in said second passageway and arranged to receive the first portion of gaseous flow so as to be driven thereby,
• f. nozzle means positioned downstream of said second and third passageways to receive the first portion of gaseous flow and discharge said first portion at a radially inward location at a relatively low velocity, and to receive the second portion of gaseous flow and discharge said second portion at a relatively higher velocity in a generally annular pattern radially outward of the radially inward location of the first portion of gaseous flow and immediately adjacent to a rear portion of said outer side surface of the housing,
• whereby said engine discharges its jet exhaust in a pattern where the second portion of gaseous flow is discharged immediately adjacent to the free air stream to alleviate noise generated by said engine.

A supersonic jet engine comprising:

• a. a housing having an upstream inlet end to receive intake air, a downstream exhaust end to discharge jet exhaust, and an outer side surface exposed directly to free stream air flow,
• b. an air inlet arranged to receive intake air at subsonic velocity and also to receive intake air at supersonic velocities and reduce said air to subsonic velocity,
• c. a compressor mounted in said housing downstream of said inlet and arranged to compress air flowing into said inlet,
• d. means defining a combustion chamber downstream of said compressor to receive compressed air therefrom and burn fuel in said compressed air to provide a gaseous flow from said combustion chamber,
• e. means defining a first generally annular passageway downstream of said combustion chamber to receive gaseous flow from said combustion chamber,
• f. means defining second and third generally coannular passageways, said second passageway being positioned radially inwardly of said third passageway and arranged to receive a first portion of gaseous flow from said first passageway, said third passageway arranged to receive a second portion of gaseous flow from said first passageway,
• g. a turbine first stage positioned in said first passageway and arranged to receive the gaseous flow from said combustion chamber so as to be driven thereby with said gaseous flow proceeding to said second and third passageways,
• h. a turbine second stage positioned in said second passageway and arranged to receive the first portion of the gaseous flow so as to be driven thereby,
• i. said turbine first stage and said turbine second stage both being operatively connected to said compressor,
• j. nozzle means positioned downstream of said second and third passageways to receive the first portion of gaseous flow and discharge said first portion at a radially inward location at a relatively low velocity, and to receive the second portion of gaseous flow and discharge said second portion at a relatively higher velocity in a generally annular pattern radially outward of the radially inward location of the first portion of gaseous flow and immediately adjacent to a rear portion of said outer side surface of the housing,
• whereby said engine discharges its jet exhaust in a pattern where the second portion of gaseous flow is discharged immediately adjacent to the free air stream to alleviate noise generated by said engine.

In a jet engine, comprising:

• a. a housing having an upstream inlet end to receive intake air, a downstream exhaust end to discharge jet exhaust, and an outer side surface exposed directly to free stream air flow,
• b. an air inlet arranged to receive intake air,
• c. a compressor mounted in said housing downstream of said inlet and arranged to compress air flowing into said inlet,
• d. means defining a combustion chamber downstream of said compressor to receive compressed air therefrom and burn fuel in said compressed air to provide a gaseous flow from said combustion chamber,
• a method of utilizing the gaseous flow from said combustion chamber to drive a turbine section so as to drive said compressor and provide a jet exhaust having a discharge pattern to alleviate noise, said method comprising:
• a. directing the gaseous flow from the combustion chamber through a first generally annular passageway downstream of the combustion chamber to drive a turbine first stage,
• b. dividing gaseous flow from the turbine first stage into first and second portions of gaseous flow,
• c. directing said first portion of gaseous flow through a second generally annular passageway positioned downstream of said first passageway at a radially inward location, and driving a turbine second stage by said first portion of gaseous flow,
• d. transmitting power from said turbine first and second stages to said compressor,
• e. directing a second portion of gaseous flow through a third generally annular passageway positioned radially outwardly of said second passageway,
• f. discharging the first and second portions of gaseous flow through nozzle means positioned downstream of the second and third passageways in a coannular pattern with the second portion of gaseous flow being positioned radially outwardly of and at a higher velocity than the first portion of gaseous flow, with the second portion of gaseous flow being immediately adjacent to a rear portion of the outer side surface of the housing,
• whereby said gaseous flow is discharged as jet exhaust in a pattern where the second portion of gaseous flow is discharged immediately adjacent to the free air stream to alleviate noise.