# US 9,752,959 B2 · Nonintrusive transceiver and method for characterizing temperature and velocity fields in a gas turbine combustor

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 9,752,959 B2
- Document ID: US9752959B2
- Status: Granted
- Kind: B2
- Application number: 14/341,924
- Filed: 2014-07-28
- Published: 2015-09-17
- Granted: 2017-09-05
- Earliest claimed: 2014-03-13
- Assignees: Siemens Energy, Inc.
- Applicants: Siemens Energy, Inc.
- Inventors: Upul P. DeSilva; Heiko Claussen
- Web page: https://patentgrep.com/patent/US9752959B2

## CPC

- F02C 3/04: having a turbine driving a compressor (power transmission arrangements F02C7/36; control of working fluid flow F02C9/16)
- G01F 1/662: {Constructional details}
- F23N 5/16: using noise-sensitive detectors
- F23R 3/002: {Wall structures (F23R3/02 and F23R3/007 take precedence)}
- F23R 2900/00013: Reducing thermo-acoustic vibrations by active means
- F02C: GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS (construction of turbines F01D; jet-propulsion plants F02K; construction of compressors or fans F04; generating combustion products of high pressure or high velocity F23R; using gas turbines in compression refrigeration plants F25B11/00)
- G01F: MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- F23N: REGULATING OR CONTROLLING COMBUSTION (control devices specially adapted for combustion apparatus in which combustion takes place in a fluidised bed of fuel or other particles F23C10/28; condition responsive controls for regulating combustion in domestic stoves with open fires for solid fuel F24B1/187)
- F23R: GENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS (fluidised bed combustion apparatus specially adapted for operation at superatmospheric pressures F23C10/16)

## Abstract

An acoustic transceiver is implemented for measuring acoustic properties of a gas in a turbine engine combustor. The transceiver housing defines a measurement chamber and has an opening adapted for attachment to a turbine engine combustor wall. The opening permits propagation of acoustic signals between the gas in the turbine engine combustor and gas in the measurement chamber. An acoustic sensor mounted to the housing receives acoustic signals propagating in the measurement chamber, and an acoustic transmitter mounted to the housing creates acoustic signals within the measurement chamber. An acoustic measurement system includes at least two such transceivers attached to a turbine engine combustor wall and connected to a controller.

## Claims

### Claim 1

A transceiver for measuring acoustic properties of a gas in a turbine engine combustor, comprising:
a housing defining a measurement chamber and having at least a first opening, the housing being adapted for attachment to a turbine engine combustor wall of the turbine engine combustor to permit propagation of acoustic signals between the gas in the turbine engine combustor and gas in the measurement chamber through the first opening;
an acoustic sensor mounted to the housing for receiving acoustic signals propagating in the measurement chamber, wherein the acoustic sensor is in communication with the measurement chamber through a second opening in the housing and wherein the measurement chamber comprises a substantially horn-shaped wave guide between the first opening and the second opening, the wave guide having a first cross sectional area near the first opening that is substantially larger than a second cross sectional area near the second opening; and
an acoustic transmitter mounted to the housing for creating acoustic signals within the measurement chamber.

### Claim 2 (depends on 1)

The transceiver of claim 1, wherein the housing is a substantially cylindrical housing having first and second ends, the first opening being at the first end of the housing, the acoustic transmitter being at the second end of the housing and the second opening being in a wall of the housing between the first and second ends.

### Claim 3 (depends on 1)

The transceiver of claim 1, wherein the acoustic transmitter is a spark generator comprising a spark gap within the measurement chamber and an electrical energy source connected to the spark gap.

### Claim 4 (depends on 3)

The transceiver of claim 3, wherein the spark generator further comprises a step-up transformer in proximity to the spark gap to step up a voltage of the electrical energy source.

### Claim 5 (depends on 1)

The transceiver of claim 1, wherein the acoustic transmitter is a whistle acoustic signal source.

### Claim 6 (depends on 5)

The transceiver of claim 5, wherein the whistle acoustic signal source is activated by a cooling gas flow outside the turbine engine combustor.

### Claim 7 (depends on 5)

The transceiver of claim 5, wherein the whistle acoustic signal source is separated from the measurement chamber by a membrane that prevents flow from the measurement chamber and conducts acoustic signals from the whistle acoustic signal source to the measurement chamber.

### Claim 8 (depends on 5)

The transceiver of claim 5, wherein the whistle acoustic signal source emits an acoustic signal having one or more dominant frequencies whereby amplitude ambiguities of the acoustic signal are spaced apart by a period longer than a range of expected time-of-flight measurements.

### Claim 9 (depends on 1)

The transceiver of claim 1, wherein the acoustic sensor is selected from a group consisting of a piezoelectric microphone, a piezoresistive microphone and a fiber optic microphone.

### Claim 10

A system for measuring properties of a gas in a turbine engine combustor, comprising:
a first housing mounted to the turbine engine combustor and defining a first measurement chamber in communication with an interior of the turbine engine combustor through a first opening in a wall of the turbine engine combustor, the first opening permitting propagation of acoustic signals between the gas in the turbine engine combustor and gas in the first measurement chamber;
a first acoustic sensor mounted to the first housing for receiving acoustic signals propagating in the first measurement chamber;
a first acoustic transmitter mounted to the first housing for creating acoustic signals within the first measurement chamber;
a controller coupled to the first acoustic sensor and the first acoustic transmitter, the controller further coupled to a second acoustic sensor arranged to receive acoustic signals propagating in the gas in the turbine engine combustor, the controller further coupled to a second acoustic transmitter for creating acoustic signals in the gas in the turbine engine combustor, the controller comprising:
a processor; and
computer readable media containing computer readable instructions that, when executed by the processor, cause the processor to perform the following operations:
transmitting by the first acoustic transmitter a first acoustic signal;
receiving by the second acoustic sensor a signal including contributions from the first acoustic signal;
transmitting by the second acoustic transmitter a second acoustic signal;
receiving by the first acoustic sensor a signal including contributions from the second acoustic signal;
determining times of flight for the first and second acoustic signals including propagation times within the turbine engine combustor;
processing the times of flight to determine the properties of the gas in the turbine engine combustor.

### Claim 11 (depends on 10)

The system of claim 10, further comprising:
a second housing mounted to the turbine engine combustor and defining a second measurement chamber in communication with the interior of the turbine engine combustor through a second opening in the wall of the turbine engine combustor, the second opening permitting propagation of acoustic signals between the gas in the turbine engine combustor and gas in the second measurement chamber;
the first and second openings defining a line-of-sound path through the turbine engine combustor;
the second acoustic sensor being mounted to the second housing for receiving acoustic signals propagating in the second measurement chamber.

### Claim 12 (depends on 11)

The system of claim 11, wherein the properties of the gas in a turbine engine combustor comprise an average speed of sound along the line-of-sound path, and wherein the operations further comprise:
determining an average temperature of the gas in the turbine engine combustor along the line-of-sound path based on the average speed of sound along the line-of-sound path.

### Claim 13 (depends on 11)

The system of claim 11, wherein the properties of the gas in the turbine engine combustor comprise an absolute gas flow velocity along the line-of-sound path, and wherein the operations further comprise:
determining an average temperature of the gas in the turbine engine combustor along the line-of-sound path based on the speed of sound along the line-of-sound path; and
determining the absolute gas flow velocity along the line-of-sound path based on the speed of sound along the line-of-sound path and further based on the temperature of the gas along the line-of-sound path.

### Claim 14 (depends on 10)

The system of claim 10, wherein the first and second openings are located in separate axial planes in a combustion zone of the turbine engine combustor containing a flame.

### Claim 15 (depends on 10)

The system of claim 10, wherein the first and second openings are located in separate axial planes in an exit zone of the turbine engine combustor proximate a turbine inlet.

### Claim 16

A method for actively monitoring gas flow characteristics in a turbine engine combustor, comprising:
transmitting, by a first acoustic transmitter, first acoustic signals in a first measurement chamber, the first measurement chamber being in communication with an interior of the turbine engine combustor through a first opening to permit propagation of the first acoustic signals from the first measurement chamber to the interior of the turbine engine combustor;
providing a first acoustic sensor that is in communication with the first measurement chamber through a second opening in the housing;
receiving, by a second acoustic sensor, the first acoustic signals in a second measurement chamber, the second measurement chamber being in communication with the interior of the turbine engine combustor through a second opening to permit propagation of the first acoustic signals from the interior of the turbine engine combustor to the second measurement chamber;
guiding the first acoustic signals from the first opening through the first measurement chamber to the second acoustic sensor by using a substantially horn-shaped wave guide comprising a shape of the first measurement chamber having a first cross sectional area near the first opening that is substantially larger than a second cross sectional area near the second opening;
determining, using a processor, a time-of-flight for the first acoustic signals along a fixed line-of-sound path in the turbine engine combustor from the first opening to the second opening; and
processing, via a processor, the time-of-flight to determine the gas flow characteristics in the turbine engine combustor.