Gas turbine pressure sensing systems and methods of assembly

1. A gas turbine engine comprising:

a compressor discharging a flow of air;

a combustor assembly positioned downstream from said compressor, said combustor comprising at least one combustion chamber;

a turbine positioned downstream from said combustor; and

a pressure sensor mounted to said combustor, said sensor comprising a sensor body, a diaphragm mounted within said sensor body, a channel extending from an open end of said sensor body to said diaphragm to directly expose said diaphragm to a pressure in said combustion chamber, and a microwave radar sensing unit secured to said sensor body, said sensing unit comprising a head positioned a distance from said diaphragm.

2. A gas turbine engine in accordance with claim 1 wherein said diaphragm is configured to deflect based on a pressure of gas in said channel.

3. A gas turbine engine in accordance with claim 2 wherein said diaphragm deflects linearly based on the gas pressure.

4. A gas turbine engine in accordance with claim 1 wherein said body further comprises a threaded portion to secure said sensor to said combustor.

5. A gas turbine engine in accordance with claim 1 wherein said sensing unit comprises external threads that mate with internal threads of said sensor body.

6. A gas turbine engine in accordance with claim 1 further comprising an interface cable coupled to said radar sensor head, and a signal conditioning unit coupled to said cable.

7. A method of assembling a gas turbine engine, said method comprising:

coupling a combustor assembly downstream from a compressor, wherein the combustor assembly includes a combustion chamber;

coupling a turbine downstream from the combustor assembly; and

coupling a pressure sensor to the combustor assembly, wherein the sensor includes a sensor body, a diaphragm mounted within the sensor body, a channel extending from an open end of the sensor body to the diaphragm to directly expose the diaphragm to a pressure in the combustion chamber, and a microwave radar sensing unit secured to the sensor body, wherein the sensing unit includes a head positioned a distance from the diaphragm.

8. A method in accordance with claim 7 wherein coupling a pressure sensor to the combustor assembly comprises coupling to the combustor assembly a pressure sensor having a diaphragm configured to deflect based on a pressure of gas in said channel.

9. A method in accordance with claim 7 wherein coupling a pressure sensor to the combustor assembly further comprises coupling to the combustor assembly a pressure sensor having a diaphragm configured to deflect linearly based on the gas pressure.

10. A method in accordance with claim 7 wherein coupling a pressure sensor to the combustor assembly comprises securing the pressure sensor to the combustor assembly using a threaded portion formed in the sensor body.

11. A method in accordance with claim 7 further comprising securing the microwave radar sensing unit to the sensor body by mating external threads formed in the sensing unit with internal threads formed in the sensor body.

12. A method in accordance with claim 7 further comprising:

coupling an interface cable to the sensor head; and

coupling a signal conditioning unit to the interface cable.

13. A method in accordance with claim 12 wherein coupling a signal conditioning unit to the interface cable comprises coupling a signal conditioning unit configured to sample a signal generated by the sensor and to store the signal in a unit memory.

14. A method for measuring a pressure within a combustion chamber of a gas turbine engine, said method comprising:

generating a signal representative of the pressure within the combustion chamber;

sampling the signal;

correlating at least one characteristic of the sampled signal to a pre-stored value, wherein the pre-stored value is associated with the pressure; and

transmitting a signal representative of the pre-stored value associated with the pressure to a controller.

15. A method in accordance with claim 14 wherein generating a signal representative of pressure within the combustion chamber comprises operating a sensor coupled to the combustion chamber such that a diaphragm of the sensor deflects according to the pressure within the combustion chamber.

16. A method in accordance with claim 14 wherein generating a signal representative of pressure within the combustion chamber comprises operating a sensor coupled to the combustion chamber such that a diaphragm of the sensor deflects linearly according to the pressure within the combustion chamber.

17. A method in accordance with claim 14 wherein correlating at least one characteristic of the sampled signal to a pre-stored value comprises:

determining a magnitude of the sampled signal; and

matching the determined magnitude to the pre-stored value.

18. A method in accordance with claim 14 wherein transmitting a signal representative of the pre-stored value associated with the pressure to a controller comprises operating a signal conditioning unit coupled to the sensor to generate the signal.

19. A method in accordance with claim 14 wherein transmitting a signal representative of the pre-stored value associated with the pressure to a controller comprises transmitting the signal to one of a control device and a display.

20. A method in accordance with claim 17 wherein matching the determined magnitude to the pre-stored values comprises comparing the determined magnitude with a plurality of pre-stored values, wherein the plurality of pre-stored values are stored in a memory of the signal conditioning unit such that each of the plurality of pre-stored values represents a possible sensor value corresponding with a respective pressure.