Active measurement of gas flow velocity or simultaneous measurement of velocity and temperature, including in gas turbine combustors
Active acoustic velocity and pyrometry-based gas flow velocity and temperature measurement, such as for monitoring of gas turbine combustors, including industrial gas turbine (IGT) combustors is incorporated into the combustion monitoring and control system by addition of an acoustic transmitter or acoustic transceiver that transmits a sound wave in a line-of-sight with a plurality of acoustic sensors, such as dynamic pressure sensors. For velocity measurement, sound transmission time-of-flight that is directed generally along the gas flow path is measured by the controller and correlated with gas flow velocity along the line-of-sight. Similarly, sound transmission time-of-flight is correlated with temperature along the line-of-sight. Path(s) of acoustic transmission serve as velocity or velocity/absolute temperature measurement. In an integrated thermoacoustic pressure-based sensor and monitoring/control system embodiment, the controller correlates velocity and, if desired, absolute active path temperatures with acoustic transmission and time-of-flight analysis techniques.
1. A method for actively monitoring gas flow velocity, comprising:
placing at least one first acoustic transmitter and at least one first acoustic sensor respectively oriented in upstream and downstream transverse locations in a gas flow path and in a distinct first line-of-sound path relative to each other, the first sensor capable of generating first sensor output signals indicative of first thermoacoustic oscillations;
coupling the at least one first transmitter and the at least one first sensor to a controller that is capable of causing the at least one first transmitter to transmit first acoustic signals within the gas flow path and capable of correlating first sensor output signals with gas flow velocity;
transmitting first acoustic signals from the at least one first acoustic transmitter;
receiving the first acoustic signals from the at least one first acoustic transmitter and generating first dynamic sensor output signals with the at least one first acoustic sensor that includes contributions of the received first acoustic signals;
determining, using a processor, a first time-of-flight for the first acoustic signals traveling along each of the first line of sound paths; and
processing, by the processor, the first time-of-flight for the first acoustic signals traveling along their first line of sound paths to determine respective gas flow velocity along each respective first line-of-sound path, wherein the processing determines respective absolute gas flow velocity including compensation for gas temperature, gas constant and speed of sound thermodynamic influences on the first time-of-flight, and
wherein the temperature compensation comprising actively monitoring temperatures in the gas flow by:
placing at least one second acoustic transmitter and at least one second acoustic sensor respectively oriented in a common axial plane in the gas flow path and in a distinct second line-of-sound path relative to each other, the second sensor capable of generating second sensor output signals indicative of second thermoacoustic oscillations;
coupling the at least one second transmitter and the at least one second sensor to the controller that is capable of causing the at least one second transmitter to transmit second acoustic signals within the gas flow path and capable of correlating the second sensor output signals time-of-flight with gas flow temperature; and
processing, by the processor, the second time-of-flight for the second acoustic signals traveling along the second line of sound paths to determine respective gas flow temperature along each respective second line-of-sound path, and
wherein the temperature compensation further comprising actively monitoring temperatures in the gas flow by:
placing at least one third acoustic transmitter and at least one third acoustic sensor respectively oriented in a common axial plane in the gas flow path downstream of the second acoustic transmitter and sensor, and in a distinct third line-of-sound path relative to each other, the third sensor capable of generating third sensor output signals indicative of third thermoacoustic oscillations;
coupling the at least one third transmitter and the at least one third sensor to the controller that is capable of causing the at least one third transmitter to transmit third acoustic signals within the gas flow path and capable of correlating the third sensor output signals time-of-flight with gas flow temperature;
processing, by the processor, the third time-of-flight for the third acoustic signals traveling along the third line of sound paths to determine respective gas flow temperature along each respective third line-of-sound path; and
interpolating, by the processor, determined respective gas flow temperatures along each respective second and third line-of-sound path to create a volumetric temperature map.
2. The method of claim 1 , the processing of the first time-of-flight described by the equation:
t
BC
=
∫
B
C
1
c
(
x
,
y
,
z
)
+
p
→
BC
·
u
→
(
x
,
y
,
z
)
ⅆ
s
where:
t BC is the time of flight from the first transmitter to the first sensor;
c is the speed of sound in the gas flow for the temperature and gas constant;
{right arrow over (p)} BC is the unit vector along the first line of sound path; and
{right arrow over (u)}(x, y, z) is velocity vector in the gas flow.
3. The method of claim 2 , further comprising determining the speed of sound c by:
substituting for the first transmitters first transceiver/transducers that are capable of transmitting and receiving acoustic signals, and generating output signals;
substituting for the first sensors second transceiver/transducers that are capable of transmitting and receiving acoustic signals and generating output signals;
coupling the respective at least one of the respective first and second transceiver/transducers to the controller that is capable of causing either to transmit first acoustic signals within the gas flow path and capable of correlating transceiver/transducer output signals time-of-flight with gas flow velocity;
transmitting first acoustic signals from the at least one first transceiver/transducer;
receiving the first acoustic signals from the at least one first transceiver/transducer and generating first dynamic sensor output signals with the at least one second transceiver/transducer that includes contributions of the received first acoustic signals;
transmitting reversed first acoustic signals from the at least one second transceiver/transducer;
receiving the reversed first acoustic signals from the at least one second transceiver/transducer and generating first reversed dynamic sensor output signals with the at least one first transceiver/transducer that includes contributions of the received reversed first acoustic signals; and
determining a first time-of-flight for the respective first and first reversed acoustic signals traveling along each of the first line of sound paths; and
processing the first time-of-flight for the respective first and reversed acoustic signals traveling along their respective first line of sound paths to determine the speed of sound c.
4. The method of claim 3 , the processing of the respective first time of flight for the respective first and first reversed acoustic signals traveling along each of the first line of sound paths to determine the speed of sound c described by the equation:
t
BC
+
t
CB
≈
∫
B
C
2
c
(
x
,
y
,
z
)
ⅆ
s
where:
t BC is the time of flight from the first transceiver/transducer to the second transceiver/transducer;
t CB is the time of flight from the second transceiver/transducer to the first transceiver/transducer;
c is the speed of sound in the gas flow for the temperature and gas constant;
{right arrow over (p)} BC is the unit vector along the first line of sound path; and
{right arrow over (u)}(x, y, z) is the velocity vector in the gas flow.
5. The method of claim 1 , the processing to determine respective absolute gas flow velocity including compensation for variations in temperature and gas constant on the speed of sound, comprising:
substituting for the first transmitters first transceiver/transducers that are capable of transmitting and receiving acoustic signals, and generating output signals;
substituting for the first sensors second transceiver/transducers that are capable of transmitting and receiving acoustic signals and generating output signals;
coupling the respective at least one of the respective first and second transceiver/transducers to the controller that is capable of causing either to transmit first acoustic signals within the gas flow path and capable of correlating transceiver/transducer output signals time-of-flight with gas flow velocity;
transmitting first acoustic signals from the at least one first transceiver/transducer;
receiving the first acoustic signals from the at least one first transceiver/transducer and generating first dynamic sensor output signals with the at least one second transceiver/transducer that includes contributions of the received first acoustic signals;
transmitting reversed first acoustic signals from the at least one second transceiver/transducer;
receiving the reversed first acoustic signals from the at least one second transceiver/transducer and generating first reversed dynamic sensor output signals with the at least one first transceiver/transducer that includes contributions of the received reversed first acoustic signals; and
determining, by the processor, a first time-of-flight for the respective first and first reversed acoustic signals traveling along each of the first line of sound paths; and
processing, by the processor, the first time-of-flight for the respective first and reversed acoustic signals traveling along their respective first line of sound paths to determine the speed of sound and using the determined speed of sound to determine respective absolute gas flow velocity along each respective first line-of-sound path.
6. A method for controlling combustion in an industrial gas turbine combustor using the gas flow velocity determined by the method of claim 1 .
7. A system for monitoring gas flow velocity in a turbine engine, comprising:
at least one first acoustic transmitter and at least one first acoustic sensor respectively oriented in upstream and downstream transverse locations in a gas flow path of a turbine engine and in a distinct first line-of-sound path relative to each other, the first sensor capable of generating first sensor output signals indicative of first thermoacoustic oscillations;
a controller, coupled to the at least one first transmitter and the at least one first sensor that is capable of causing the at least one first transmitter to transmit first acoustic signals within the gas flow path and capable of correlating first sensor output signals with gas flow velocity, by:
transmitting first acoustic signals from the at least one first acoustic transmitter;
receiving the first acoustic signals from the at least one first acoustic transmitter and generating first dynamic sensor output signals with the at least one first acoustic sensor that includes contributions of the received first acoustic signals;
determining, using a processor, a first time-of-flight for the first acoustic signals traveling along each of the first line of sound paths; and
processing, by the processor, the first time-of-flight for the first acoustic signals traveling along their first line of sound paths to determine respective gas flow velocity along each respective first line-of-sound path,
wherein the processing determines respective absolute gas flow velocity including compensation for gas temperature, gas constant and speed of sound thermodynamic influences on the first time-of-flight, and
wherein the temperature compensation comprising actively monitoring temperatures in the gas flow by:
placing at least one second acoustic transmitter and at least one second acoustic sensor respectively oriented in a common axial plane in the gas flow path and in a distinct second line-of-sound path relative to each other, the second sensor capable of generating second sensor output signals indicative of second thermoacoustic oscillations;
coupling the at least one second transmitter and the at least one second sensor to the controller that is capable of causing the at least one second transmitter to transmit second acoustic signals within the gas flow path and capable of correlating the second sensor output signals time-of-flight with gas flow temperature; and
processing, by the processor, the second time-of-flight for the second acoustic signals traveling along the second line of sound paths to determine respective gas flow temperature along each respective second line-of-sound path, and
wherein the temperature compensation further comprising actively monitoring temperatures in the gas flow by:
placing at least one third acoustic transmitter and at least one third acoustic sensor respectively oriented in a common axial plane in the gas flow path downstream of the second acoustic transmitter and sensor, and in a distinct third line-of-sound path relative to each other, the third sensor capable of generating third sensor output signals indicative of third thermoacoustic oscillations;
coupling the at least one third transmitter and the at least one third sensor to the controller that is capable of causing the at least one third transmitter to transmit third acoustic signals within the gas flow path and capable of correlating the third sensor output signals time-of-flight with gas flow temperature;
processing, by the processor, the third time-of-flight for the third acoustic signals traveling along the third line of sound paths to determine respective gas flow temperature along each respective third line-of-sound path; and
interpolating, by the processor, determined respective gas flow temperatures along each respective second and third line-of-sound path to create a volumetric temperature map.
8. The system of claim 7 , including determination of absolute gas flow velocity by compensating for temperature thermodynamic influences on the time-of-flight, further comprising:
at least one second acoustic transmitter and at least one second acoustic sensor respectively oriented in a common axial plane in the turbine gas flow path and in a distinct second line-of-sound path relative to each other, the second sensor capable of generating second sensor output signals indicative of second thermoacoustic oscillations;
the controller coupled to the at least one second transmitter and the at least one second sensor and capable of:
causing the at least one second transmitter to transmit second acoustic signals within the gas flow path; and
processing, by the processor, the second time-of-flight for the second acoustic signals traveling along the second line of sound paths to determine respective gas flow temperature along each respective second line-of-sound path; and
using the determined respective gas flow temperatures in compensating for temperature influence on the first time-of-flight.
9. The system of claim 8 further comprising first and second planar arrays of n transceiver/transducers incorporating the respective first and second transmitters and sensors, the planar arrays oriented generally normal to mutually spaced along the gas flow path in opposed relationship, each transceiver/transducer in the first planar array transmitting:
the first acoustic signals to (n−1) transceiver/transducers in the second planar array; and
the second acoustic signals to (n−1) transceiver/transducers in the first planar array.
10. The system of claim 7 , the controller processing of the first time-of-flight described by the equation:
t
BC
=
∫
B
C
1
c
(
x
,
y
,
z
)
+
p
→
BC
·
u
→
(
x
,
y
,
z
)
ⅆ
s
where:
t BC is the time-of-flight from the first transmitter to the first sensor;
c is the speed of sound in the gas flow for the temperature and gas constant;
{right arrow over (p)} BC is the unit vector along the first line of sound path; and
{right arrow over (u)}(x, y, z) is velocity vector in the gas flow.
11. The system of claim 10 , further comprising the controller determining the speed of sound c by:
substituting for the first transmitters first transceiver/transducers that are capable of transmitting and receiving acoustic signals, and generating output signals;
substituting for the first sensors second transceiver/transducers that are capable of transmitting and receiving acoustic signals and generating output signals;
coupling the respective at least one of the respective first and second transceiver/transducers to the controller that is capable of causing either to transmit first acoustic signals within the gas flow path and capable of correlating transceiver/transducer output time-of-flight signals with gas flow velocity;
transmitting first acoustic signals from the at least one first transceiver/transducer;
receiving the first acoustic signals from the at least one first transceiver/transducer and generating first dynamic sensor output signals with the at least one second transceiver/transducer that includes contributions of the received first acoustic signals;
transmitting reversed first acoustic signals from the at least one second transceiver/transducer;
receiving the reversed first acoustic signals from the at least one second transceiver/transducer and generating first reversed dynamic sensor output signals with the at least one first transceiver/transducer that includes contributions of the received reversed first acoustic signals; and
determining, by the processor, a first time-of-flight for the respective first and first reversed acoustic signals traveling along each of the first line of sound paths; and
processing, by the processor, the first time-of-flight for the respective first and reversed acoustic signals traveling along their respective first line of sound paths to determine the speed of sound c.
12. The system of claim 11 , the controller processing of the respective first time of flight for the respective first and first reversed acoustic signals traveling along each of the first line of sound paths to determine the speed of sound c described by the equation:
t
BC
+
t
CB
≈
∫
B
C
2
c
(
x
,
y
,
z
)
ⅆ
s
where:
t BC is the time-of-flight from the first transceiver/transducer to the second transceiver/transducer;
t CB is the time-of-flight from the second transceiver/transducer to the first transceiver/transducer;
c is the speed of sound in the gas flow for the temperature and gas constant;
{right arrow over (p)} BC is the unit vector along the first line of sound path; and
{right arrow over (u)}(x, y, z) is the velocity vector in the gas flow.
13. A gas turbine engine apparatus, comprising:
a compressor section;
a combustor section including a plurality of combustors, each combustor having an injector system for regulating fuel/air mixture;
a turbine section; and
a system for monitoring gas flow velocity in the turbine engine, comprising:
at least one first acoustic transmitter and at least one first acoustic sensor respectively oriented in upstream and downstream transverse locations in a gas flow path of a turbine engine and in a distinct first line-of-sound path relative to each other, the first sensor capable of generating first sensor output signals indicative of first thermoacoustic oscillations;
a controller, coupled to the at least one first transmitter and the at least one first sensor that is capable of causing the at least one first transmitter to transmit first acoustic signals within the gas flow path and capable of correlating first sensor output signals with gas flow velocity, by:
transmitting first acoustic signals from the at least one first acoustic transmitter;
receiving the first acoustic signals from the at least one first acoustic transmitter and generating first dynamic sensor output signals with the at least one first thermoacoustic sensor that includes contributions of the received first acoustic signals;
determining, using a processor, a first time-of-flight for the first acoustic signals traveling along each of the first line of sound paths; and
processing, by the processor, the first time-of-flight for the first acoustic signals traveling along their first line of sound paths to determine respective gas flow velocity along each respective first line-of-sound path,
wherein the processing determines respective absolute gas flow velocity including compensation for gas temperature, gas constant and speed of sound thermodynamic influences on the first time-of-flight, and
wherein the temperature compensation comprising actively monitoring temperatures in the gas flow by:
placing at least one second acoustic transmitter and at least one second acoustic sensor respectively oriented in a common axial plane in the gas flow path and in a distinct second line-of-sound path relative to each other, the second sensor capable of generating second sensor output signals indicative of second thermoacoustic oscillations;
coupling the at least one second transmitter and the at least one second sensor to the controller that is capable of causing the at least one second transmitter to transmit second acoustic signals within the gas flow path and capable of correlating the second sensor output signals time-of-flight with gas flow temperature; and
processing, by the processor, the second time-of-flight for the second acoustic signals traveling along the second line of sound paths to determine respective gas flow temperature along each respective second line-of-sound path, and
wherein the temperature compensation further comprising actively monitoring temperatures in the gas flow by:
placing at least one third acoustic transmitter and at least one third acoustic sensor respectively oriented in a common axial plane in the gas flow path downstream of the second acoustic transmitter and sensor, and in a distinct third line-of-sound path relative to each other, the third sensor capable of generating third sensor output signals indicative of third thermoacoustic oscillations;
coupling the at least one third transmitter and the at least one third sensor to the controller that is capable of causing the at least one third transmitter to transmit third acoustic signals within the gas flow path and capable of correlating the third sensor output signals time-of-flight with gas flow temperature;
processing, by the processor, the third time-of-flight for the third acoustic signals traveling along the third line of sound paths to determine respective gas flow temperature along each respective third line-of-sound path; and
interpolating, by the processor, determined respective gas flow temperatures along each respective second and third line-of-sound path to create a volumetric temperature map.
14. The apparatus of claim 13 , including determination of absolute gas flow velocity by compensating for temperature thermodynamic influences on the time-of-flight, further comprising:
at least one second acoustic transmitter and at least one second acoustic sensor respectively oriented in a common axial plane in the turbine gas flow path and in a distinct second line-of-sound path relative to each other, the second sensor capable of generating second sensor output signals indicative of second thermoacoustic oscillations;
the controller coupled to the at least one second transmitter and the at least one second sensor and capable of:
causing the at least one second transmitter to transmit second acoustic signals within the gas flow path; and
processing, by the processor, the second time-of-flight for the second acoustic signals traveling along the second line of sound paths to determine respective gas flow temperature along each respective second line-of-sound path; and
using the determined respective gas flow temperatures in compensating for temperature on the first time-of-flight.
15. The apparatus of claim 14 , further comprising first and second planar arrays of n transceiver/transducers incorporating the respective first and second transmitters and sensors, the planar arrays oriented generally normal to and mutually spaced along the gas flow path in opposed relationship, each transceiver/transducer in the first planar array transmitting:
the first acoustic signals to (n−1) transceiver/transducers in the second planar array; and
the second acoustic signals to (n−1) transceiver/transducers in the first planar array.
16. The system of claim 13 , the controller processing of the first time-of-flight described by the equation:
t
BC
=
∫
B
C
1
c
(
x
,
y
,
z
)
+
p
→
BC
·
u
→
(
x
,
y
,
z
)
ⅆ
s
where:
t BC is the time of flight from the first transmitter to the first sensor;
c is the speed of sound in the gas flow for the temperature and gas constant;
{right arrow over (p)} BC is the unit vector along the first line of sound path; and
{right arrow over (u)}(x, y, z) is velocity vector in the gas flow.
17. The apparatus of claim 16 , further comprising the controller determining the speed of sound c by:
substituting for the first transmitters first transceiver/transducers that are capable of transmitting and receiving acoustic signals, and generating output signals;
substituting for the first sensors second transceiver/transducers that are capable of transmitting and receiving acoustic signals and generating output signals;
coupling the respective at least one of the respective first and second transceiver/transducers to the controller that is capable of causing either to transmit first acoustic signals within the gas flow path and capable of correlating transceiver/transducer output signals time-of-flight with gas flow velocity;
transmitting first acoustic signals from the at least one first transceiver/transducer;
receiving the first acoustic signals from the at least one first transceiver/transducer and generating first dynamic sensor output signals with the at least one second transceiver/transducer that includes contributions of the received first acoustic signals;
transmitting reversed first acoustic signals from the at least one second transceiver/transducer;
receiving the reversed first acoustic signals from the at least one second transceiver/transducer and generating first reversed dynamic sensor output signals with the at least one first transceiver/transducer that includes contributions of the received reversed first acoustic signals; and
determining, by the processor, a first time-of-flight for the respective first and first reversed acoustic signals traveling along each of the first line of sound paths; and
processing, by the processor, the first time-of-flight for the respective first and reversed acoustic signals traveling along their respective first line of sound paths to determine the speed of sound c, described by the equation:
t
BC
+
t
CB
≈
∫
B
C
2
c
(
x
,
y
,
z
)
ⅆ
s
where:
t BC is the time of flight from the first transceiver/transducer to the second transceiver/transducer;
t CB is the time of flight from the second transceiver/transducer to the first transceiver/transducer;
c is the speed of sound in the gas flow for the temperature and gas constant;
{right arrow over (p)} BC is the unit vector along the first line of sound path; and
{right arrow over (u)}(x, y, z) is the velocity vector in the gas flow.