Physical amount measuring system, integration system, physical amount measuring method, and program

Abstract

To measure the concentration of a gas included in a mixed gas discharged after combustion with good accuracy.SOLUTION: A physical amount measuring system 1 comprises a flow path 101, a pair of ultrasonic echo sounder transducers 11, 12, and a concentration measuring unit 204. In the flow path 101 flows a mixed gas containing at least third gas generated by combustion of a first gas and a second gas in a combustor 3. The pair of ultrasonic echo sounder transducers 11, 12 are arranged to transmit / receive an ultrasonic wave so that the ultrasonic wave crosses the flow of the mixed gas in the flow path 101. When combustion is incomplete, the mixed gas contains first and second unburnt gases. The concentration measuring unit 204 measures the concentration of each of the first gas, the second gas, and the third gas by using the propagation time of the ultrasonic wave obtained by transmission / reception of an ultrasonic wave in the pair of ultrasonic echo sounder transducers 11, 12, the temperature of the mixed gas, the equivalent ratio of the first gas to the second gas flowing into the combustor 3.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure generally relates to a physical quantity measurement system, an integrated system, a physical quantity measurement method, and a program, and more particularly to a physical quantity measurement system having a flow path through which a mixed gas flows, an integrated system, a physical quantity measurement method used in the physical quantity measurement system, and a program. [Background technology]

[0002] BACKGROUND ART Conventionally, there is known a measuring device that can measure the concentration of gas contained in a mixed gas even when the mixed gas is in a high humidity state (see Patent Document 1).

[0003] Patent Document 1 describes a hydrogen flow concentration meter (physical quantity measurement system) that measures the concentration of gases contained in a mixed gas by using the propagation time of ultrasonic waves and the measured values ​​of a temperature sensor, a pressure sensor, and a relative humidity sensor. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2023-28677 Summary of the Invention [Problem to be solved by the invention]

[0005] Incidentally, gas may be combusted and the concentration of the gas contained in the mixed gas discharged after combustion may be measured. The concentration meter of Patent Document 1 does not take into account the combustion of the gas, i.e., does not take into account the inclusion of unburned gas. Therefore, when the concentration meter of Patent Document 1 is used to measure the concentration of the gas contained in the mixed gas discharged after combustion, an error may occur.

[0006] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a physical quantity measurement system, an integrated system, a physical quantity measurement method, and a program that can accurately measure the concentration of gas contained in a mixed gas that is discharged after combustion. [Means for solving the problem]

[0007] A physical quantity measuring system according to one aspect of the present disclosure includes a flow path, a pair of ultrasonic transmitter-receivers, and a concentration measurement unit. A mixed gas containing at least a third gas generated by burning a first gas and a second gas in a combustor flows through the flow path. The pair of ultrasonic transmitter-receivers transmit and receive ultrasonic waves and are arranged so that the ultrasonic waves intersect the flow of the mixed gas in the flow path. The concentration measurement unit measures the concentrations of gases contained in the mixed gas. When combustion is incomplete, the mixed gas contains the first gas and the second gas that are unburned. The concentration measurement unit measures the concentrations of the first gas, the second gas, and the third gas using the propagation time of the ultrasonic waves obtained by transmitting and receiving the ultrasonic waves between the pair of ultrasonic transmitter-receivers, the temperature of the mixed gas, and the equivalence ratio between the first gas and the second gas flowing into the combustor.

[0008] An integrated system according to one aspect of the present disclosure includes the physical quantity measurement system and the combustor.

[0009] A physical quantity measuring method according to one aspect of the present disclosure is used in a physical quantity measuring system including a flow path and a pair of ultrasonic transmitter-receivers. A mixed gas containing at least a third gas generated by combusting a first gas and a second gas in a combustor flows through the flow path. The pair of ultrasonic transmitter-receivers transmit and receive ultrasonic waves and are arranged so that the ultrasonic waves intersect the flow of the mixed gas in the flow path. The physical quantity measuring method includes a concentration measuring step. In the concentration measuring step, the concentrations of gases contained in the mixed gas are measured. When combustion is incomplete, the mixed gas contains the first gas and the second gas that are unburned. In the concentration measuring step, the concentrations of the first gas, the second gas, and the third gas are measured using the propagation time of the ultrasonic waves obtained by transmitting and receiving the ultrasonic waves between the pair of ultrasonic transmitter-receivers, the temperature of the mixed gas, and the equivalence ratio between the first gas and the second gas flowing into the combustor.

[0010] A program according to one aspect of the present disclosure is a program for causing a computer system to execute the physical quantity measuring method. [Effects of the Invention]

[0011] According to the present disclosure, the concentration of gas contained in the mixed gas discharged after combustion can be measured with high accuracy. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a system diagram showing the configuration of an integrated system including a physical quantity measuring system according to an embodiment. [Figure 2] FIG. 2 is a block diagram showing the configuration of the physical quantity measuring system. [Figure 3] FIG. 3 is a system diagram showing the configuration of the physical quantity measuring system. [Figure 4] FIG. 4 is a cross-sectional view of a flow path main body provided in the physical quantity measuring system in the XY plane. [Figure 5] FIG. 5 is a graph illustrating how to determine the flow coefficient. [Figure 6] FIG. 6 is a flowchart showing the operation of the integrated system. [Figure 7] FIG. 7 is a flowchart showing the operation of the physical quantity measuring system. [Figure 8] FIG. 8 is a flowchart showing a concentration measurement process performed by the physical quantity measurement system. [Figure 9] FIG. 9 is a flowchart showing the sound speed calculation process performed in the concentration measurement process. [Figure 10] FIG. 10 is a flowchart showing a concentration calculation process performed in the concentration measurement process. [Figure 11] FIG. 11 is a flowchart showing a flow rate measurement process performed by the physical quantity measurement system. [Figure 12] FIG. 12 is a flowchart showing a flow coefficient calculation process performed in the flow measurement process in the embodiment. [Figure 13] FIG. 13 is a system diagram showing the configuration of an integrated system according to the first modification. [Figure 14] FIG. 14 is a system diagram showing the configuration of a physical quantity measuring system according to the second modification. DETAILED DESCRIPTION OF THE INVENTION

[0013] The embodiments and modifications described below are merely examples of the present disclosure, and the present disclosure is not limited to the embodiments and modifications. Various modifications other than the following embodiments and modifications are possible depending on the design, etc., as long as they do not deviate from the technical concept of the present disclosure.

[0014] (Embodiment) A physical quantity measuring system 1 according to this embodiment will be described below with reference to FIGS.

[0015] (1) Overview As shown in Fig. 1, the integrated system 1000 of this embodiment includes a physical quantity measurement system 1 and a combustor 3. The combustor 3 is, for example, a gas turbine, and generates power by combusting a first gas and a second gas. Here, the first gas is, for example, a hydrocarbon Cn H m The second gas is, for example, oxygen O2.

[0016] The integrated system 1000 further includes a control system 2. The control system 2 controls the flow rates of the first gas (hydrocarbon) and the second gas (oxygen) flowing into the combustor 3.

[0017] The physical quantity measurement system 1 measures the concentration of at least one of a plurality of gases contained in a mixed gas discharged from a combustor 3 (see FIG. 1). For example, a mixed gas containing at least a third gas (carbon dioxide CO2) and water vapor (water) HO generated by burning a first gas (hydrocarbon) and a second gas (oxygen) flows through a flow path 101. Furthermore, if combustion is incomplete, the mixed gas contains unburned first gas (hydrocarbon) and second gas (oxygen).

[0018] As shown in FIGS. 2 and 4 , the physical quantity measuring system 1 of this embodiment includes a flow path 101, a pair of ultrasonic transmitters / receivers 11 and 12, and a concentration measuring unit 204. A mixed gas containing at least a third gas generated by combusting a first gas and a second gas flows through the flow path 101. The pair of ultrasonic transmitters / receivers 11 and 12 transmit and receive ultrasonic waves and are arranged so that the ultrasonic waves cross the flow of the mixed gas in the flow path. The concentration measuring unit 204 measures the concentrations of gases contained in the mixed gas. When combustion is incomplete, the mixed gas contains unburned first and second gases. The concentration measuring unit 204 measures the concentrations of the first, second, and third gases using the propagation time of ultrasonic waves obtained by transmitting and receiving ultrasonic waves between the pair of ultrasonic transmitters / receivers 11 and 12, the temperature of the mixed gas, and the equivalence ratio between the first and second gases flowing into the combustor 3.

[0019] According to this configuration, by using the equivalence ratio, it is possible to take into account the excess gas, and therefore it is possible to measure with high accuracy the concentration of the gas contained in the mixed gas that flows out after combustion.

[0020] In this embodiment, the combustor 3 is configured as a gas turbine as an example, but is not limited to this configuration. The combustor 3 may be an industrial furnace, a boiler, or the like.

[0021] (2) Composition The configuration of the integrated system 1000 will be described below.

[0022] (2.1) Physical Quantity Measurement System The detailed configuration of the physical quantity measuring system 1 will be described below with reference to FIGS.

[0023] 2, the physical quantity measurement system 1 includes a flow path main body 10 and a processing device 20. The physical quantity measurement system 1 measures, as physical quantities, the concentration of a gas contained in a mixed gas flowing through the flow path main body 10, the flow rate of the mixed gas, and the flow rate of a gas contained in the mixed gas. Furthermore, the concentration measured by the physical quantity measurement system 1 here is, for example, a volume concentration.

[0024] An X-axis, a Y-axis, and a Z-axis are defined for the flow path body 10 (see FIG. 3). The X-axis is an axis along the longitudinal direction of the flow path body 10, i.e., an axis along the direction in which the mixed gas flows. The Y-axis is an axis perpendicular to the X-axis, for example, an axis along the depth direction of the flow path body 10. The Z-axis is an axis perpendicular to both the X-axis and the Y-axis, for example, an axis along the height direction of the flow path body 10. FIG. 4 is a cross-sectional view of the flow path body 10 in a plane defined by the X-axis and the Y-axis (XY plane). Note that in FIG. 4, the pair of ultrasonic transmitter / receivers 11 and 12 and the temperature sensor 14 are not shown in cross section.

[0025] (2.1.1) Flow path body A mixed gas flows through the flow path main body 10. As shown in FIG. 2, the flow path main body 10 has a pair of ultrasonic transmitter / receivers 11 and 12, a pressure sensor 13, a temperature sensor 14, and a humidity sensor 15. Furthermore, as shown in FIG. 3, the flow path main body 10 has a main body portion 100. In the following description, the ultrasonic transmitter / receiver 11 may be referred to as a first ultrasonic transmitter / receiver 11, and the ultrasonic transmitter / receiver 12 may be referred to as a second ultrasonic transmitter / receiver 12.

[0026] The main body 100 is formed in a substantially rectangular shape. A flow path 101 through which the fluid to be measured (gas mixture) flows is formed in the center of the main body 100 (see FIG. 4). A first opening 110 and a second opening 111 are provided at both ends in the longitudinal direction of the main body 100. Specifically, the first opening 110 and the second opening 111 are provided on both side surfaces of the main body 100 that face each other in the longitudinal direction. The first opening 110 and the second opening 111 are connected by the flow path 101. The gas mixture flows in from the first opening 110, passes through the flow path 101, and flows out from the second opening 111.

[0027] The pair of ultrasonic transmitters and receivers 11, 12 transmit and receive ultrasonic waves. The pair of ultrasonic transmitters and receivers 11, 12 are arranged so that the ultrasonic waves cross the flow of the mixed gas in the flow channel 101. Specifically, the first ultrasonic transmitter and receiver 11 transmits (transmits) ultrasonic waves toward the second ultrasonic transmitter and receiver 12. The first ultrasonic transmitter and receiver 11 receives (receives) ultrasonic waves transmitted from the second ultrasonic transmitter and receiver 12. The second ultrasonic transmitter and receiver 12 transmits (transmits) ultrasonic waves toward the first ultrasonic transmitter and receiver 11. The second ultrasonic transmitter and receiver 12 receives (receives) ultrasonic waves transmitted from the first ultrasonic transmitter and receiver 11. The first ultrasonic transmitter and receiver 11 and the second ultrasonic transmitter and receiver 12 are arranged upstream and downstream at both ends of the shorter side of the flow channel 101 so that the ultrasonic signals cross the flow of the mixed gas. The first ultrasonic transmitter / receiver 11 and the second ultrasonic transmitter / receiver 12 are arranged on opposite sides of the flow channel 101 in the short direction, upstream and downstream, so that ultrasonic signals cross the flow of the mixed gas. Specifically, the first ultrasonic transmitter / receiver 11 is arranged upstream and the second ultrasonic transmitter / receiver 12 is arranged downstream, facing each other (see FIGS. 3 and 4). In the opposing direction between the first ultrasonic transmitter / receiver 11 and the second ultrasonic transmitter / receiver 12, an ultrasonic propagation path 106 that propagates ultrasonic waves is formed (see FIG. 4). The ultrasonic propagation path 106 is inclined at an angle θ with respect to the flow channel 101 (see FIG. 4).

[0028] The pressure sensor 13 measures the pressure of the mixed gas flowing through the flow path 101 .

[0029] The temperature sensor 14 is, for example, a thermocouple, and measures the temperature of the gas mixture flowing through the flow path 101.

[0030] The humidity sensor 15 measures the humidity of the mixed gas flowing through the flow path 101 .

[0031] (2.1.2) Processing equipment As shown in FIG. 2, the processing device 20 includes a first communication unit 21, a second communication unit 22, a third communication unit 23, a fourth communication unit 24, a storage unit 25, and a control unit 26.

[0032] The processing device 20 includes, for example, a computer system having one or more processors and a memory. The processor executes a program stored in the memory, causing the computer system to function as the control unit 26. The program executed by the processor is pre-recorded in the memory of the computer system here, but may also be provided by being recorded on a non-transitory recording medium such as a memory card, or via a telecommunications line such as the Internet.

[0033] The first communication unit 21 is a communication interface for communicating with the first ultrasonic transmitter / receiver 11 and the second ultrasonic transmitter / receiver 12. The second communication unit 22 is a communication interface for communicating with the pressure sensor 13, the temperature sensor 14, and the humidity sensor 15. The third communication unit 23 is a communication interface for communicating with the control system. The fourth communication unit 24 is a communication interface for communicating with a user device (not shown) or the like. The user device is equipped with a display unit such as a liquid crystal display, and is a device for notifying a user of measurement results and the like in the physical quantity measurement system 1.

[0034] The storage unit 25 is configured with a device selected from a ROM (Read Only Memory), a RAM (Random Access Memory), an EEPROM (Electrically Erasable Programmable Read Only Memory), etc. The storage unit 25 stores information used for measuring physical quantities.

[0035] As shown in FIG. 2, the control unit 26 includes a first signal processing unit 201, a second signal processing unit 202, a water vapor pressure measuring unit 203, a concentration measuring unit 204, a flow rate measuring unit 205, and an output processing unit 206.

[0036] The first signal processing unit 201 performs processing related to communication between the first ultrasonic transmitter / receiver 11 and the second ultrasonic transmitter / receiver 12 .

[0037] For example, when transmitting ultrasonic waves from the first ultrasonic transmitter / receiver 11 to the second ultrasonic transmitter / receiver 12, the first signal processing unit 201 outputs a signal instructing the first ultrasonic transmitter / receiver 11 to transmit ultrasonic waves to the first ultrasonic transmitter / receiver 11 via the first communication unit 21. When transmitting ultrasonic waves from the second ultrasonic transmitter / receiver 12 to the first ultrasonic transmitter / receiver 11, the first signal processing unit 201 outputs a signal instructing the second ultrasonic transmitter / receiver 12 to transmit ultrasonic waves to the second ultrasonic transmitter / receiver 12 via the first communication unit 21.

[0038] The first signal processing unit 201 also calculates the first propagation time (propagation time of the ultrasonic waves in the forward direction) t up Specifically, the first signal processing unit 201 measures the first propagation time t based on the time when the ultrasonic wave is transmitted from the first ultrasonic transmitter / receiver 11 and the time when the ultrasonic wave transmitted from the first ultrasonic transmitter / receiver 11 is received by the second ultrasonic transmitter / receiver 12. up Measure.

[0039] The first signal processing unit 201 also calculates a second propagation time t of the ultrasonic wave transmitted from the second ultrasonic transmitter / receiver 12 to the first ultrasonic transmitter / receiver 11 (the propagation time of the ultrasonic wave in the reverse direction) dwSpecifically, the first signal processing unit 201 measures the second propagation time t based on the time when the ultrasonic wave is transmitted from the second ultrasonic transmitter / receiver 12 and the time when the ultrasonic wave transmitted from the second ultrasonic transmitter / receiver 12 is received by the first ultrasonic transmitter / receiver 11. dw Measure.

[0040] The first signal processing unit 201 calculates the first propagation time t up and the second propagation time t dw The average time between these two is calculated as the propagation time t.

[0041] The second signal processing unit 202 receives signals output from each sensor and performs predetermined processing on the received signals. When the second signal processing unit 202 receives a signal output from the pressure sensor 13, it performs predetermined signal processing on the received signal to determine the pressure P measured by the pressure sensor 13. When the second signal processing unit 202 receives a signal output from the temperature sensor 14, it performs predetermined signal processing on the received signal to determine the temperature T measured by the temperature sensor 14. When the second signal processing unit 202 receives a signal output from the humidity sensor 15, it performs predetermined signal processing on the received signal to determine the humidity H measured by the humidity sensor 15.

[0042] The water vapor pressure measuring unit 203 measures the water vapor pressure of the water vapor contained in the mixed gas flowing through the flow path 101. The water vapor pressure measuring unit 203 measures the water vapor pressure P of the water vapor using the temperature of the mixed gas measured by the temperature sensor 14 and the humidity of the mixed gas measured by the humidity sensor 15. w Specifically, the water vapor pressure measuring unit 203 measures the water vapor pressure P w Here, T in Equation 1 is the temperature of the mixed gas measured by the temperature sensor 14, and H is the humidity of the mixed gas measured by the humidity sensor 15.

[0043]

number

[0044] The concentration measurement unit 204 measures the concentrations of gases contained in the mixed gas. The concentration measurement unit 204 measures a water vapor concentration, which is the concentration of water vapor contained in the mixed gas, and a gas concentration, which is the concentration of a gas contained in the mixed gas but different from water vapor. The concentration measurement unit 204 measures the concentrations of a first gas (hydrocarbon), a second gas (oxygen), and a third gas (carbon dioxide) as the gas concentrations.

[0045] The concentration measurement unit 204 measures the pressure P of the mixed gas measured by the pressure sensor 13 and the water vapor pressure P measured by the water vapor pressure measurement unit 203. w Using this, the water vapor concentration x w Specifically, the concentration measurement unit 204 measures the water vapor concentration x using the following equation 2: w Ask for.

[0046]

number

[0047] The concentration measurement unit 204 measures the concentrations of the first gas, the second gas, and the third gas using the propagation time t of the ultrasonic waves obtained by transmitting and receiving the ultrasonic waves between the pair of ultrasonic transmitters and receivers 11 and 12, the temperature T of the mixed gas, and the equivalence ratio between the first gas and the second gas flowing into the combustor 3. More specifically, the concentration measurement unit 204 calculates the measured water vapor concentration x w , the propagation time t of the ultrasonic wave, the temperature T of the mixed gas, and the equivalence ratio, are used to measure the concentrations of the first gas, the second gas, and the third gas. w The concentrations of hydrocarbons, oxygen, and carbon dioxide are measured using the propagation time t of the ultrasonic waves obtained by transmitting and receiving ultrasonic waves between a pair of ultrasonic transmitters and receivers 11 and 12, the temperature T of the mixed gas, and the equivalence ratio of hydrocarbons to oxygen flowing into the combustor 3.

[0048] The equivalence ratio is the actual fuel-air ratio divided by the stoichiometric fuel-air ratio.

[0049] The fuel-air ratio is a value obtained by dividing the first gas (hydrocarbon) flowing into the combustor 3 by the second gas (oxygen) flowing into the combustor 3. The stoichiometric fuel-air ratio is a ratio of the number of molecules of two gases used in a combustion reaction equation expressed by a chemical formula of combustion. The stoichiometric fuel-air ratio is a value obtained by dividing the number of molecules of the first gas (hydrocarbon) by the number of molecules of the second gas (oxygen). For example, the reaction equation for combustion of the first gas (hydrocarbon) and the second gas (oxygen) is expressed by the following reaction formula (1).

[0050] [ka]

[0051] In this case, the equivalence ratio φ between the first gas (hydrocarbon) and the second gas (oxygen) in this embodiment is expressed by the following equation 3.

[0052]

number

[0053] Q1 shown in Equation 3 is the flow rate of hydrocarbons when they flow into the combustor 3, and Q2 shown in Equation 3 is the flow rate of oxygen when oxygen flows into the combustor 3.

[0054] Here, the sound speed c of the mixed gas, the propagation time t of the ultrasonic waves, the length L of the ultrasonic propagation path 106 (the distance between the first ultrasonic transducer 11 and the second ultrasonic transducer 12), the molecular weight M of the mixed gas, and the specific heat ratio γ (=c p / c v ), the temperature T of the mixed gas, and the gas constant R, the relationship shown in Equation 4 holds true. p is the constant pressure molar specific heat. v is the molar specific heat at constant volume.

[0055]

number

[0056] In this embodiment, when combustion is incomplete, the mixed gas contains a first gas (hydrocarbon), a second gas (oxygen), a third gas (carbon dioxide), and water vapor. Here, the molecular weight of the hydrocarbon is M1, and the constant pressure specific heat is c p1 , specific heat at constant volume is c v1 The molecular weight of oxygen is M2, and the specific heat at constant pressure is c p2 , specific heat at constant volume is c v2 Also, let the molecular weight of carbon dioxide be M3 and the specific heat at constant pressure be c p3 , specific heat at constant volume is c v3 and the molecular weight of water vapor is M w , specific heat at constant pressure is c pw , specific heat at constant volume is c vw Furthermore, the hydrocarbon concentration is x1, the oxygen concentration is x2, the carbon dioxide concentration is x3, and the water vapor concentration is x w In this case, the following equations 5 to 7 hold true.

[0057]

number

[0058]

number

[0059]

number

[0060] By using numbers 5 to 7, number 4 can be transformed into number 8.

[0061]

number

[0062] The concentration measurement unit 204 receives the flow rate Q1 of hydrocarbons flowing into the combustor 3 and measured, and the flow rate Q2 of oxygen flowing into the combustor 3 and measured, from the control system 2 via the third communication unit 23. The concentration measurement unit 204 calculates the equivalence ratio φ using the received flow rate Q1 of hydrocarbons, flow rate Q2 of oxygen, and the above-mentioned equation 3.

[0063] When the equivalence ratio is greater than 1, there is an excess of hydrocarbons. Therefore, taking into account the excess and unburned hydrocarbons, the above-mentioned reaction formula (1) can be transformed into the following reaction formula (2).

[0064] [ka]

[0065] Here, s represents the unburned fraction. Also, the coefficient "(φ-1)" in reaction formula (2) represents the excess hydrocarbon C n H m The coefficients "s" and "s(n+m / 4)" represent the number of molecules of unburned hydrocarbons C n H m The coefficients "(1-s)n" and "(1-s)(m / 2)" represent the number of molecules of carbon dioxide CO2 and water vapor H2O produced by combustion. The excess hydrocarbon C n H m The number of molecules of hydrocarbons C that are not used in combustion corresponds to the number of molecules of oxygen O2. n H m The number of molecules of unburned hydrocarbons C n H m The number of molecules of hydrocarbons C and oxygen O2 that are components that would normally be used in combustion but were not actually burned is n H m and the number of oxygen O2 molecules. The excess hydrocarbon C n H m is not actually burned.

[0066] Furthermore, the ratio (proportion) of hydrocarbon, oxygen, and carbon dioxide is expressed by the following equation 9 based on reaction formula (2). Furthermore, equation 9 can be transformed into the following equation 10.

[0067]

number

[0068]

number

[0069] Equation 10 does not take into account the water vapor generated during combustion. Therefore, if we take into account the water vapor generated during combustion, Equation 10 can be transformed into the following Equation 11.

[0070]

number

[0071] Equation 11 represents the concentration ratio of hydrocarbon, oxygen, and carbon dioxide in a gas mixture containing hydrocarbon, oxygen, carbon dioxide, and water vapor. That is, the hydrocarbon concentration x1, oxygen concentration x2, and carbon dioxide concentration x3 are expressed by the following equations 12 to 14.

[0072]

number

[0073]

number

[0074]

number

[0075] The concentration measurement unit 204 measures the hydrocarbon C n H mThe unburned fraction s is solved using the information on the above, the calculated equivalence ratio φ, and Equation 8, Equation 12 to Equation 14. Here, the hydrocarbon C n H m The information about is the values ​​of n and m.

[0076] The concentration measurement unit 204 measures the hydrocarbon C n H m Using the information on the above, the calculated equivalence ratio φ, the calculated unburned fraction s, and equations 12 to 14, the hydrocarbon concentration (hydrocarbon concentration) x1, the oxygen concentration (oxygen concentration) x2, and the carbon dioxide concentration (carbon dioxide concentration) x3 are calculated.

[0077] When the equivalence ratio is less than 1, there is an excess of oxygen. Taking the excess and unburned oxygen into consideration, the above-mentioned reaction formula (1) can be transformed into the following reaction formula (3).

[0078] [ka]

[0079] Here, s represents the unburned fraction. In addition, the coefficient "(1-φ)(n+m / 4)" in reaction formula (3) represents the number of excess oxygen O2 molecules, and the coefficients "s" and "s(n+m / 4)" represent the unburned hydrocarbon C n H m The coefficients "(1-s)n" and "(1-s)(m / 2)" represent the number of molecules of carbon dioxide CO2 and water vapor H2O produced by combustion. The number of molecules of excess oxygen O2 is the number of molecules of hydrocarbon C n H m The number of oxygen O2 molecules that are not used in combustion corresponds to the number of unburned hydrocarbons C n H m The number of molecules of hydrocarbons C and oxygen O2 that are components that would normally be used in combustion but were not actually burned is n H m and the number of oxygen O2 molecules. The excess oxygen O2 is not actually burned.

[0080] Furthermore, the ratio (proportion) of hydrocarbon, oxygen, and carbon dioxide is expressed by the following equation 15 based on reaction formula (3). Furthermore, equation 15 can be transformed into the following equation 16.

[0081]

number

[0082]

number

[0083] Equation 16 does not take into account the water vapor generated during combustion. Therefore, if water vapor generated during combustion is taken into account, Equation 16 can be transformed into the following Equation 17.

[0084]

number

[0085] Equation 17 represents the concentration ratio of hydrocarbon, oxygen, and carbon dioxide in a gas mixture containing hydrocarbon, oxygen, carbon dioxide, and water vapor. That is, the hydrocarbon concentration x1, oxygen concentration x2, and carbon dioxide concentration x3 are expressed by the following equations 18 to 20.

[0086]

number

[0087]

number

[0088]

number

[0089] The concentration measurement unit 204 measures the hydrocarbon C n Hm The unburned fraction s is solved using the information on the above, the calculated equivalence ratio φ, and equations 8, 18, and 20. Here, the hydrocarbon C n H m The information about is the values ​​of n and m.

[0090] The concentration measurement unit 204 measures the hydrocarbon C n H m Using the information on the above, the calculated equivalence ratio φ, the calculated unburned fraction s, and Equations 18 to 20, the hydrocarbon concentration x1, the oxygen concentration x2, and the carbon dioxide concentration x3 are calculated.

[0091] When the equivalence ratio is the value "1", the concentration measurement unit 204 sets φ=1 and calculates the hydrocarbon concentration x1, the oxygen concentration x2, and the carbon dioxide concentration x3 using the above equations 8 and 12 to 14 or the above equations 8 and 18 to 20.

[0092] As described above, when the equivalence ratio is greater than 1, the concentration measurement unit 204 calculates the hydrocarbon concentration x1, the oxygen concentration x2, and the carbon dioxide concentration x3 using Equations 12 to 14 obtained based on Equation 11. That is, when the equivalence ratio is greater than 1, the concentration measurement unit 204 measures the concentrations of the first gas, the second gas, and the third gas based on the ratio between the number of molecules of the first gas (hydrocarbon) including the excess and unburned portion, the number of molecules of the unburned second gas (oxygen), and the number of molecules of the generated third gas (carbon dioxide).

[0093] When the equivalence ratio is smaller than 1, the concentration measurement unit 204 calculates the hydrocarbon concentration x1, the oxygen concentration x2, and the carbon dioxide concentration x3 using Equations 18 to 20 obtained based on Equation 17. That is, when the equivalence ratio is smaller than 1, the concentration measurement unit 204 measures the concentrations of the first gas, the second gas, and the third gas based on the ratio between the number of molecules of the unburned first gas (hydrocarbon), the number of molecules of the second gas (oxygen) obtained by adding the surplus and unburned amounts, and the number of molecules of the generated third gas (carbon dioxide).

[0094] When the equivalence ratio is 1, the concentration measurement unit 204 calculates the hydrocarbon concentration x1, the oxygen concentration x2, and the carbon dioxide concentration x3 using Equations 12 to 14 obtained based on Equation 11 or Equations 18 to 20 obtained based on Equation 17. That is, when the equivalence ratio is 1, the concentration measurement unit 204 measures the concentrations of the first gas, the second gas, and the third gas based on the ratio between the number of molecules of the unburned first gas (hydrocarbon), the number of molecules of the unburned second gas (oxygen), and the number of molecules of the generated third gas (carbon dioxide).

[0095] The flow rate measurement unit 205 measures the flow rate of the mixed gas using the concentrations of the first gas (hydrocarbon), the second gas (oxygen), and the third gas (carbon dioxide), the propagation time of the ultrasonic waves, the temperature of the mixed gas, and the pressure of the mixed gas. More specifically, the flow rate measurement unit 205 measures the flow rate of the mixed gas using the concentrations of the first gas (hydrocarbon), the second gas (oxygen), the third gas (carbon dioxide), and water vapor, the propagation time of the ultrasonic waves, the temperature of the mixed gas, and the pressure of the mixed gas. The flow rate measurement unit 205 calculates the flow rate Q of the mixed gas using the following equations 21 and 22. Equation 21 is a formula for calculating the tentative flow rate Q0. The tentative flow rate Q0 is calculated by multiplying the cross-sectional area S of the flow path 101 by the flow velocity V. In addition, the flow velocity V, the length L of the ultrasonic propagation path 106 (the distance between the first ultrasonic transmitter / receiver 11 and the second ultrasonic transmitter / receiver 12), the first propagation time t up , the second propagation time t dw From the relationship between the angle θ of the ultrasonic wave propagation path 106 and the flow path 101, "Q0=SV" can be transformed into the right side of Equation 21. Here, R K is the flow coefficient.

[0096]

number

[0097]

number

[0098] In addition, the flow coefficient R Kis the kinematic viscosity ν, characteristic length D, and flow velocity V m where Re is the Reynolds number. That is, the Reynolds number Re is calculated by the formula "Re=V m The characteristic length D is, for example, the length (height) of the flow channel 101 in the Z direction. The function f(Re) is a predetermined function. m is the flow velocity corresponding to the flow rate measured by the standard device during calibration (hereinafter referred to as the reference flow rate) performed as a preliminary evaluation.

[0099]

number

[0100] Here, the kinetic viscosity ν is a value that depends on the temperature T in the flow path 101, the concentration of each gas (hydrocarbon, oxygen, carbon dioxide, water vapor) contained in the mixed gas, and the pressure P. Furthermore, because the kinetic viscosity ν is "kinetic viscosity = viscosity / density," it can be obtained from the following equation (24). The transformation from the middle side to the right side of equation (24) is due to the gas's equation of state, "pressure P · volume = number of moles · gas constant R · temperature T," and relational equation 1, "density = mass / volume," resulting in relational equation 2, "density = (molecular weight M · pressure P) / (gas constant R · temperature T)." In other words, from the gas's equation of state and relational equation 1, the density ρ can be expressed in terms of the molecular weight M, pressure P, temperature T, and gas constant R. Here, the pressure P is the pressure measured by the pressure sensor 13, and the temperature T is the temperature measured by the temperature sensor 14. Furthermore, the density ρ is determined by the gas's concentration, temperature, and pressure. Therefore, in relational equation 2, the molecular weight M is a function (see equation 5) with the concentration as a variable.

[0101]

number

[0102] μ(x, T) in Equation 24 can be calculated from the viscosity of each gas (hydrocarbon, oxygen, carbon dioxide, water vapor) contained in the mixed gas. The flow rate measurement unit 205 calculates the viscosity of each gas using a known method. The flow rate measurement unit 205 calculates the viscosity of each gas using the viscosity of each gas calculated using a known method and the previously calculated concentrations of each gas (hydrocarbon concentration x1, oxygen concentration x2, carbon dioxide concentration x3, water vapor concentration x w ) to calculate the viscosity μ of the gas mixture.

[0103] where, the flow coefficient R K We will explain how to calculate this.

[0104] Flow coefficient R K is the virtual flow rate Q0 and the reference flow rate Q m Using the above, it is expressed as the following equation 25. Here, the reference flow rate Q m is the flow rate measured by the standard device at the time of calibration.

[0105]

number

[0106] The Reynolds number Re is the reference flow rate Q m In equation 26, ν represents the kinematic viscosity of the mixed gas, D represents the characteristic length, and S represents the cross-sectional area of ​​the flow path 101. m is the reference flow rate Q measured by the standard device during calibration m is the flow velocity corresponding to

[0107]

number

[0108] The processing device 20 calculates the reference flow rate Q using Equations 25 and 26. m The flow coefficient R was calculated using the Reynolds number Re and the provisional flow rate Q0 obtained from the measurement value when K Multiple combinations of (Re, R K ) is calculated as a preliminary evaluation, and the Reynolds number Re and the flow coefficient R KThe relational expression is calculated and stored in advance.

[0109] Furthermore, using Equations 25 and 26, the Reynolds number Re and the flow coefficient R K The characteristic length D and cross-sectional area S are known values ​​in the physical quantity measurement system 1, and the kinematic viscosity ν and provisional flow rate Q0 are values ​​that have already been calculated. That is, the flow coefficient R K is expressed as a linear function using the Reynolds number Re. In other words, Equation 27 is expressed as a function of the Reynolds number Re and the flow coefficient R K and the coefficient is a value ((νS) / (Q0D)) based on the tentative flow rate Q0 and the kinematic viscosity ν of the mixed gas.

[0110]

number

[0111] The flow rate measurement unit 205 measures the Reynolds number Re and the flow coefficient R obtained by the preliminary evaluation. K Using the relational expression that expresses the relationship between K Specifically, the flow rate measurement unit 205 calculates the flow rate coefficient R corresponding to the provisional flow rate Q0 by determining the intersection A0 between the graph G1 (see FIG. 5) expressed by the relational expression obtained by the pre-evaluation and the graph G2 (see FIG. 5) expressed by the equation 27. K It is more preferable that the flow velocity measured by the flow rate measuring unit 205 is calculated at a value where the Reynolds number is in the laminar flow region, since this stabilizes the measured value.

[0112] The flow rate measurement unit 205 calculates the flow rate coefficient R K and Equation 22 to calculate the flow rate Q. The provisional flow rate Q0 is calculated based on the propagation time (first propagation time t up and the second propagation time t dw ) and the flow rate Q is calculated using the flow coefficient R obtained from the Reynolds number Re. Kand the tentative flow rate Q0. Therefore, it can be said that the flow rate measurement unit 205 measures the flow rate Q of the mixed gas in the flow path 101 using the Reynolds number Re and the propagation time of the ultrasonic waves obtained from the pair of ultrasonic transmitter-receivers 11 and 12.

[0113] Here, the kinematic viscosity ν appears in both Equation 23 and Equation 26. That is, the flow coefficient R K is a value based on the kinematic viscosity ν of the mixed gas. Also, according to equation 26, the Reynolds number Re uses the kinematic viscosity ν as a coefficient. In other words, the flow coefficient R K is a value obtained by using a linear function of the Reynolds number, with a coefficient based on the kinematic viscosity ν of the mixed gas. More specifically, the flow coefficient R K is a value obtained from a linear function of the Reynolds number, the coefficient of which is based on the kinematic viscosity ν of the mixed gas, and a relational expression that expresses the relationship between the Reynolds number obtained by a pre-evaluation and the flow coefficient.

[0114] The treatment device 20 uses the Reynolds number Re and the flow coefficient R calculated by the pre-evaluation instead of using the relational expression obtained by the pre-evaluation. K Multiple combinations with (Re, R K ) may be used.

[0115] The output processing unit 206 outputs the concentrations of the first gas and the second gas measured by the concentration measuring unit 204 to the control system 2 that controls the flow rates of the first gas and the second gas flowing into the combustor 3.

[0116] (2.2) Control System The control system 2 controls the flow rates of the first gas (hydrocarbon) and the second gas (oxygen) flowing into the combustor 3.

[0117] The control system 2 is configured to be able to communicate with the physical quantity measurement system 1. The control system 2 receives the measurement results, that is, the concentration of the first gas (hydrocarbon concentration) and the concentration of the second gas (oxygen concentration), from the physical quantity measurement system 1. The control system 2 controls (adjusts) the flow rates of the first gas and the second gas flowing into the combustor 3 based on the received concentration of the first gas (hydrocarbon concentration) and the concentration of the second gas (oxygen concentration). That is, the control system 2 performs feedback control based on the measurement results (hydrocarbon concentration, oxygen concentration) of the physical quantity measurement system 1. This makes it possible to reduce the amount of the first gas and the second gas that remains unburned, that is, to reduce the unburned fraction s.

[0118] As shown in FIG. 1, the control system 2 includes a first inlet 501, a second inlet 502, a first switch 503, and a second switch 504.

[0119] The first inlet device 501 causes the first gas (hydrocarbon) to flow into the combustor 3. The first inlet device 501 is equipped with a first flow meter. The first flow meter measures a flow rate Q1 of the first gas flowing into the combustor 3. The first inlet device 501 transmits the flow rate Q1 of the first gas measured by the first flow meter to the processing device 20 of the physical quantity measurement system 1.

[0120] The second inlet device 502 introduces the second gas (oxygen) into the combustor 3. The second inlet device 502 is equipped with a second flow meter. The second flow meter measures the flow rate Q2 of the second gas flowing into the combustor 3. The second inlet device 502 transmits the flow rate Q2 of the second gas measured by the second flow meter to the processing device 20 of the physical quantity measurement system 1.

[0121] The first switch 503 controls the flow rate Q1 of the first gas flowing into the combustor 3 based on the concentration (hydrocarbon concentration) of the first gas, which is the measurement result of the physical quantity measurement system 1. The first switch 503 is equipped with a first on-off valve. For example, when the concentration (hydrocarbon concentration) of the first gas is high, the first switch 503 controls the first on-off valve so as to decrease the flow rate Q1 of the first gas flowing into the combustor 3. When the concentration (hydrocarbon concentration) of the first gas is low, the first switch 503 controls the first on-off valve so as to increase the flow rate Q1 of the first gas flowing into the combustor 3.

[0122] The second switch 504 controls the flow rate Q2 of the second gas flowing into the combustor 3 based on the concentration (oxygen concentration) of the second gas, which is the measurement result of the physical quantity measurement system 1. The second switch 504 is equipped with a second on-off valve. For example, when the concentration (oxygen concentration) of the second gas is high, the second switch 504 controls the second on-off valve so as to decrease the flow rate Q2 of the second gas flowing into the combustor 3. When the concentration (oxygen concentration) of the second gas is low, the second switch 504 controls the second on-off valve so as to increase the flow rate Q2 of the second gas flowing into the combustor 3.

[0123] (2.3) Combustor The combustor 3 is, for example, a gas turbine, and generates power by combusting a first gas (hydrocarbon) and a second gas (oxygen). The combustor 3 combusts the first gas and the second gas flowed in from the control system 2 to generate power.

[0124] (3) Operation (3.1) Overall overview Here, the operation of the integrated system 1000 will be described with reference to FIG.

[0125] The control system 2 performs an inflow process (step S1). The control system 2 causes a first gas (hydrocarbon) and a second gas (oxygen) to flow into the combustor 3. More specifically, the first inflow device 501 of the control system 2 causes the first gas to flow into the combustor 3, and the second inflow device 502 of the control system 2 causes the second gas to flow into the combustor 3. Furthermore, the control system 2 outputs a flow rate Q1 of the first gas measured by the first flow meter and a flow rate Q2 of the first gas measured by the second flow meter to the processing device 20 of the physical quantity measurement system 1.

[0126] The combustor 3 performs a combustion process (step S2). The combustor 3 combusts the first gas and the second gas flowed in from the control system 2 to generate power.

[0127] The physical quantity measurement system 1 performs a measurement process (step S3). The physical quantity measurement system 1 measures the concentrations of gases contained in the mixed gas and the flow rate of the mixed gas, using the mixed gas that is input or output from the combustor 3. For example, the physical quantity measurement system 1 measures the concentrations of a first gas, a second gas, and a third gas contained in the mixed gas and the flow rate of the mixed gas, using the mixed gas that is input or output from the combustor 3.

[0128] The physical quantity measurement system 1 outputs the measurement results, that is, the concentration of the first gas (hydrocarbon concentration) and the concentration of the second gas (oxygen concentration), to the control system 2. Based on the concentration of the first gas (hydrocarbon concentration) and the concentration of the second gas (oxygen concentration) received from the physical quantity measurement system 1, the control system 2 controls the first gas (hydrocarbon) and the second gas (oxygen) flowing into the combustor 3, and performs the inflow process shown in step S1.

[0129] (3.2) Measurement processing Here, the operation of the measurement process shown in step S3 of FIG. 6 will be described with reference to FIG.

[0130] The first signal processing unit 201 performs a first measurement process (step S11). Specifically, the first signal processing unit 201 measures a first propagation time t upThe first signal processing unit 201 also measures the second propagation time t dw Furthermore, the first signal processing unit 201 measures the first propagation time t up and the second propagation time t dw Calculate the propagation time t, which is the average time between

[0131] The second signal processing unit 202 performs a second measurement process (step S12). Specifically, the second signal processing unit 202 determines the pressure P measured by the pressure sensor 13 based on the signal output from the pressure sensor 13. The second signal processing unit 202 determines the temperature T measured by the temperature sensor 14 based on the signal output from the temperature sensor 14. The second signal processing unit 202 determines the humidity H measured by the humidity sensor 15 based on the signal output from the humidity sensor 15.

[0132] The water vapor pressure measurement unit 203 performs a water vapor pressure measurement process (step S13). The water vapor pressure measurement unit 203 executes the water vapor pressure measurement process to measure the water vapor pressure P w Specifically, the water vapor pressure measurement unit 203 acquires the temperature T of the mixed gas measured by the temperature sensor 14 and the humidity H of the mixed gas measured by the humidity sensor 15 from the second signal processing unit 202. The water vapor pressure measurement unit 203 calculates the water vapor pressure P using the acquired temperature T of the mixed gas and humidity H of the mixed gas and the above-mentioned equation (1). w Measure (calculate).

[0133] The concentration measurement unit 204 performs a water vapor concentration measurement process (step S14). The concentration measurement unit 204 measures the water vapor pressure P w , the pressure P of the mixed gas measured by the pressure sensor 13, and the above-mentioned equation 2 are used to calculate the water vapor concentration x w Measure.

[0134] The concentration measurement unit 204 performs a gas concentration measurement process (step S15). The concentration measurement unit 204 executes the gas concentration measurement process to calculate (measure) the concentrations of the first gas (hydrocarbon), the second gas (oxygen), and the third gas (carbon dioxide) contained in the mixed gas.

[0135] The flow rate measurement unit 205 executes a flow rate measurement process to calculate the flow rate Q of the mixed gas (step S16).

[0136] The output processing unit 206 performs output processing (step S17). The output processing unit 206 outputs the concentration of the first gas (hydrocarbon concentration) and the concentration of the second gas (oxygen concentration) calculated in step S15 to the control system 2. Based on the received concentrations of the first gas and the second gas, the control system 2 controls the flow rates of the first gas and the second gas flowing into the combustor 3 so as to minimize the unburned fraction s.

[0137] (3.3) Gas concentration measurement processing Here, the gas concentration measurement process shown in step S15 of FIG. 7 will be described with reference to FIG.

[0138] The concentration measurement unit 204 performs a sound velocity calculation process (step S101). The concentration measurement unit 204 calculates the sound velocity c based on the propagation time t of the ultrasonic wave calculated by the first signal processing unit 201. Here, the propagation time t is the first propagation time t up and the second propagation time t dw This is the average time.

[0139] The concentration measurement unit 204 performs a gas concentration calculation process (step S102). The concentration measurement unit 204 calculates the sound velocity c calculated based on the ultrasonic wave propagation time t, the water vapor concentration x calculated in the water vapor concentration measurement process (step S14 shown in FIG. 7), and the water vapor concentration t. w , and the temperature T and equivalence ratio φ measured by the temperature sensor 14, the concentrations of the first gas (hydrocarbon), the second gas (oxygen), and the third gas (carbon dioxide) are calculated (measured).

[0140] (3.4) Sound speed calculation process Here, the sound speed calculation process shown in step S101 of FIG. 8 will be described with reference to FIG.

[0141] The concentration measurement unit 204 receives the distance L (the distance between the first ultrasonic transmitter / receiver 11 and the second ultrasonic transmitter / receiver 12) stored in advance in the storage unit 25 and the first propagation time t up and the second propagation time t dw and are acquired (step S151).

[0142] The concentration measurement unit 204 measures the first propagation time t up and the second propagation time t dw The propagation time t, which is the average time between the above and the above, is calculated (step S152).

[0143] The concentration measurement unit 204 calculates the sound speed c using the distance L acquired in step S151, the propagation time t calculated in step S152, and Equation 4 described above (step S153).

[0144] (3.5) Gas concentration calculation process Here, the concentration calculation process shown in step S102 in FIG. 8 will be described with reference to FIG.

[0145] The concentration measurement unit 204 acquires the temperature T determined in the second measurement process (step S12 shown in FIG. 7) (step S161).

[0146] The concentration measurement unit 204 calculates the sound velocity c calculated in the sound velocity calculation process (step S101 shown in FIG. 8) and the water vapor concentration x calculated in the water vapor concentration measurement process (step S14 shown in FIG. 7). w is acquired (step S162).

[0147] The concentration measurement unit 204 acquires each parameter stored in advance in the storage unit 25 (step S163). The concentration measurement unit 204 acquires the gas constant R, the molecular weight M1 of the first gas, the molecular weight M2 of the second gas, the molecular weight M3 of the third gas, the molecular weight M of water vapor, w , the constant pressure molar specific heat (cp1 ,c p2 ,c p3 ,c pw ), and the constant-volume molar specific heat (c v1 ,c v2 ,c v3 ,c vw ), and are taken as parameters.

[0148] The concentration measurement unit 204 calculates the equivalence ratio φ (step S164). The concentration measurement unit 204 calculates the equivalence ratio φ using the flow rate Q1 of the first gas (hydrocarbon) and the flow rate Q2 of the second gas (oxygen) received from the control system 2.

[0149] The concentration measurement unit 204 determines whether the equivalence ratio φ is greater than 1 (step S165).

[0150] When it is determined that the equivalence ratio φ is greater than 1 ("Yes" in step S165), the concentration measurement unit 204 performs a first concentration calculation process (step S166). n H m The unburned fraction s is calculated using the information on the above, the calculated equivalence ratio φ, and the above-mentioned equations 8, 12, and 14. Here, the hydrocarbon C n H m The information about is the values ​​of n and m. The concentration measurement unit 204 measures the hydrocarbon C n H m Using the information on the above, the calculated equivalence ratio φ, the calculated unburned fraction s, and Equations 12 to 14, the hydrocarbon concentration x1, the oxygen concentration x2, and the carbon dioxide concentration x3 are calculated.

[0151] If it is determined that the equivalence ratio φ is not greater than 1 ("No" in step S165), the concentration measurement unit 204 determines whether the equivalence ratio φ is less than 1 (step S167).

[0152] When it is determined that the equivalence ratio φ is less than 1 ("Yes" in step S167), the concentration measurement unit 204 performs a second concentration calculation process (step S168). n H m The unburned fraction s is calculated using the information on the above, the calculated equivalence ratio φ, and the above-mentioned equations 8, 18 to 20. Here, the hydrocarbon C n H m The information about is the values ​​of n and m. The concentration measurement unit 204 measures the hydrocarbon C n H m Using the information on the above, the calculated equivalence ratio φ, the calculated unburned fraction s, and Equations 18 to 20, the hydrocarbon concentration x1, the oxygen concentration x2, and the carbon dioxide concentration x3 are calculated.

[0153] When it is determined that the equivalence ratio φ is not less than 1, that is, the equivalence ratio φ is 1 ("No" in step S167), the concentration measurement unit 204 performs a third concentration calculation process (step S169). Specifically, the concentration measurement unit 204 sets φ=1 and calculates the hydrocarbon C n H m Alternatively, the concentration measurement unit 204 calculates the hydrocarbon concentration x1, the oxygen concentration x2, and the carbon dioxide concentration x3 stored in the storage unit 25 by setting φ=1. n H m Using the information above and Equations 8 and 18 to 20, the hydrocarbon concentration x1, oxygen concentration x2, and carbon dioxide concentration x3 are calculated.

[0154] (3.6) Flow measurement processing Here, the flow rate measurement process shown in step S16 in FIG. 7 will be described with reference to FIG.

[0155] The flow rate measurement unit 205 calculates the first propagation time t up and the second propagation time t dw and are acquired (step S201).

[0156] The flow rate measuring unit 205 acquires each parameter stored in advance in the storage unit 25 (step S202). The flow rate measuring unit 205 acquires the cross-sectional area S of the flow path 101, the length L of the ultrasonic propagation path 106 (the distance L between the first ultrasonic transmitter / receiver 11 and the second ultrasonic transmitter / receiver 12), and the angle θ at which the ultrasonic propagation path 106 is inclined with respect to the flow path 101 as the parameters.

[0157] The flow rate measurement unit 205 performs a tentative flow rate calculation process (step S203). Specifically, the flow rate measurement unit 205 calculates the first propagation time t up and the second propagation time t dw Using the cross-sectional area S, length L, and angle θ obtained in step S202 and equation (21), a tentative flow rate Q0 of the mixed gas is calculated (step S203).

[0158] The flow rate measurement unit 205 performs a flow rate coefficient calculation process (step S204). By performing the flow rate coefficient calculation process, the flow rate measurement unit 205 calculates the flow rate coefficient R K Calculate.

[0159] The flow rate measurement unit 205 calculates the tentative flow rate Q0 and the flow rate coefficient R K and Equation 22 to calculate the flow rate Q of the mixed gas (step S205).

[0160] (3.7) Flow coefficient calculation process Here, the flow coefficient calculation process shown in step S204 of FIG. 11 will be described with reference to FIG.

[0161] The flow rate measurement unit 205 acquires the temperature T measured by the temperature sensor 14 and the pressure P measured by the pressure sensor 13 as measurement values ​​(step S251).

[0162] The flow rate measurement unit 205 acquires the concentrations of the first gas (hydrocarbon), the second gas (oxygen), the third gas (carbon dioxide), and the water vapor contained in the mixed gas (step S252). That is, the flow rate measurement unit 205 acquires the hydrocarbon concentration x1, the oxygen concentration x2, the carbon dioxide concentration x3, and the water vapor concentration x w Get.

[0163] The flow rate measuring unit 205 acquires each parameter stored in advance in the storage unit 25 (step S253). The flow rate measuring unit 205 acquires the characteristic length D and the cross-sectional area S of the flow path 101 as parameters. Furthermore, the flow rate measuring unit 205 acquires the viscosity of each gas (hydrocarbon, oxygen, carbon dioxide, water vapor) contained in the mixed gas.

[0164] The flow rate measurement unit 205 measures the viscosity of each of hydrocarbon, oxygen, carbon dioxide, and water vapor, and the water vapor concentration x w Using the hydrocarbon concentration x1, the oxygen concentration x2, and the carbon dioxide concentration x3, the viscosity μ of the mixed gas containing hydrocarbons, oxygen, carbon dioxide, and water vapor is calculated (step S254).

[0165] The flow rate measurement unit 205 measures the water vapor concentration x w Using the concentration of the first gas (hydrocarbon concentration x1), the concentration of the second gas (oxygen concentration x2), and the concentration of the third gas (carbon dioxide concentration x3) and equation 24, the kinematic viscosity ν of the mixed gas containing the first gas, the second gas, the third gas, and water vapor is calculated (step S255).

[0166] The flow rate measurement unit 205 obtains the intersection of the graph expressed by the relational expression obtained by the preliminary evaluation and the graph expressed by Equation 27, thereby obtaining the flow rate coefficient R corresponding to the provisional flow rate Q0. K is calculated (step S256).

[0167] (4) Advantages As described above, the physical quantity measuring system 1 of this embodiment includes the flow path 101, a pair of ultrasonic transmitters / receivers 11 and 12, and a concentration measuring unit 204. A mixed gas containing at least a third gas generated by combusting a first gas and a second gas in the combustor 3 flows through the flow path 101. The pair of ultrasonic transmitters / receivers 11 and 12 transmit and receive ultrasonic waves and are arranged so that the ultrasonic waves cross the flow of the mixed gas in the flow path 101. The concentration measuring unit 204 measures the concentrations of the gases contained in the mixed gas. When combustion is incomplete, the mixed gas contains unburned first and second gases. The concentration measuring unit 204 measures the concentrations of the first gas, the second gas, and the third gas using the propagation time of ultrasonic waves obtained by transmitting and receiving ultrasonic waves between the pair of ultrasonic transmitters / receivers 11 and 12, the temperature of the mixed gas, and the equivalence ratio between the first gas and the second gas flowing into the combustor 3.

[0168] According to this configuration, by using the equivalence ratio, it is possible to take into account the excess gas, and therefore it is possible to measure with high accuracy the concentration of the gas contained in the mixed gas that flows out after combustion.

[0169] (5) Variations Modifications are listed below. The modifications described below can be applied in appropriate combination with the above-described embodiment.

[0170] (5.1) Variation 1 It is not essential that the physical quantity measuring system 1 includes the humidity sensor 15 .

[0171] When the physical quantity measurement system 1 does not include the humidity sensor 15, the integrated system 1000 further includes a dehumidifier 4 between the combustor 3 and the physical quantity measurement system 1 of the first modification, as shown in FIG.

[0172] The dehumidifier 4 removes water vapor contained in the mixed gas flowing out from the combustor 3, and the mixed gas not containing water vapor flows into the physical quantity measuring system 1 of the first modified example.

[0173] Since the mixed gas flowing through the flow path 101 of the physical quantity measuring system 1 of the first modified example does not contain water vapor, the processing device 20 of the physical quantity measuring system 1 of the first modified example does not measure the water vapor pressure.

[0174] In Modification 1, since the mixed gas does not contain water vapor, the above-mentioned Equation 8 can be modified to the following Equation 28.

[0175]

number

[0176] Furthermore, when the equivalence ratio φ is greater than 1, the hydrocarbon concentration x1, oxygen concentration x2, and carbon dioxide concentration x3 are expressed by the following equations 29 to 31 based on the above-mentioned equation 10. When the equivalence ratio φ is smaller than 1, the hydrocarbon concentration x1, oxygen concentration x2, and carbon dioxide concentration x3 are expressed by the following equations 32 to 34 based on the above-mentioned equation 16.

[0177]

number

[0178]

number

[0179]

number

[0180]

number

[0181]

number

[0182]

number

[0183] When the equivalence ratio φ is greater than 1, the concentration measurement unit 204 of the physical quantity measurement system 1 of the first modified example calculates the hydrocarbon C n H m The unburned fraction s is solved using the information on the above, the calculated equivalence ratio φ, and Equations 28 to 31. Here, the hydrocarbon C n H m The information about is the values ​​of n and m. n H m Using the information on the above, the calculated equivalence ratio φ, the calculated unburned fraction s, and Equations 29 to 31, the hydrocarbon concentration (hydrocarbon concentration) x1, the oxygen concentration (oxygen concentration) x2, and the carbon dioxide concentration (carbon dioxide concentration) x3 are calculated.

[0184] When the equivalence ratio φ is smaller than 1, the concentration measurement unit 204 of the physical quantity measurement system 1 of the first modified example calculates the hydrocarbon C n H m The unburned fraction s is solved using the information on the above, the calculated equivalence ratio φ, and equations 28, 32, and 34. Here, the hydrocarbon C n H m The information about is the values ​​of n and m. n H m Using the information on the above, the calculated equivalence ratio φ, the calculated unburned fraction s, and Equations 32 to 34, the hydrocarbon concentration (hydrocarbon concentration) x1, the oxygen concentration (oxygen concentration) x2, and the carbon dioxide concentration (carbon dioxide concentration) x3 are calculated.

[0185] When the equivalence ratio is "1", the concentration measurement unit 204 of the physical quantity measurement system 1 of Modification 1 sets φ to 1 and calculates the hydrocarbon concentration x1, the oxygen concentration x2, and the carbon dioxide concentration x3 using the above equations 28 to 31 or using equations 28 and 32 to 34.

[0186] (5.2) Variation 2 In the present disclosure, at least one of the pressure sensor 13, the temperature sensor 14, and the humidity sensor 15 is not an essential component of the physical quantity measuring system 1.

[0187] When the physical quantity measurement system 1 does not include the pressure sensor 13, the pressure of the mixed gas flowing through the flow path 101 may be obtained from an external device 30 shown in Fig. 14. That is, when the pressure of the mixed gas flowing through the flow path 101 is known by another means, the physical quantity measurement system 1 does not necessarily need to include the pressure sensor 13. The physical quantity measurement system 1 may obtain the pressure of the mixed gas flowing through the flow path 101, which is known by another means, from the external device 30 and use it as a measurement value.

[0188] When the physical quantity measurement system 1 does not include the temperature sensor 14, it may acquire the temperature of the mixed gas flowing through the flow path 101 from the external device 30. In other words, when the temperature of the mixed gas flowing through the flow path 101 is known by another means, the physical quantity measurement system 1 does not necessarily need to include the temperature sensor 14. The physical quantity measurement system 1 may acquire the temperature of the mixed gas flowing through the flow path 101, which is known by another means, from the external device 30 and use it as a measurement value.

[0189] When the physical quantity measurement system 1 does not include the humidity sensor 15, it may acquire the humidity of the mixed gas flowing through the flow path 101 from the external device 30. In other words, when the humidity of the mixed gas flowing through the flow path 101 is known by another means, the physical quantity measurement system 1 does not necessarily need to include the humidity sensor 15. The physical quantity measurement system 1 may acquire the humidity of the mixed gas flowing through the flow path 101, which is known by another means, from the external device 30 and use it as a measurement value.

[0190] The concentration measurement unit 204 of the physical quantity measurement system 1 of Modification 2 calculates the water vapor pressure using the humidity and temperature of the mixed gas. The concentration measurement unit 204 of the physical quantity measurement system 1 of Modification 2 calculates the water vapor concentration using the calculated water vapor pressure and the pressure of the mixed gas.

[0191] In this case, if the physical quantity measurement system 1 of variant example 2 does not have any of the pressure sensor 13, the temperature sensor 14, and the humidity sensor 15, the concentration measurement unit 204 of variant example 2 acquires all of the pressure, humidity, and temperature of the mixed gas from the external device 30.

[0192] Alternatively, the physical quantity measurement system 1 of Modification 2 may measure one or two of the pressure, temperature, and humidity of the mixed gas. In this case, the physical quantity measurement system 1 of Modification 2 further includes one or two sensors that perform measurements according to one or two of the measurement targets of the mixed gas pressure, temperature, and humidity of the mixed gas. That is, the physical quantity measurement system 1 of Modification 2 further includes one or two sensors from among a pressure sensor 13 that measures the pressure of the mixed gas, a temperature sensor 14 that measures the temperature of the mixed gas, and a humidity sensor 15 that measures the humidity of the mixed gas, according to one or two of the measurement targets of the mixed gas pressure, temperature, and humidity of the mixed gas. The concentration measurement unit 204 of Modification 2 externally acquires the pressure, temperature, and humidity of the mixed gas that are not the measurement targets of the mixed gas pressure, temperature, and humidity of the mixed gas. With this configuration, some of the pressure, temperature, and humidity of the mixed gas can be acquired from the sensors, and the rest can be acquired externally.

[0193] (5.3) Variation 3 The flow channel body 10 may further include one or more partition plates. The one or more partition plates divide the flow channel 101 into multiple sections in the height direction (Z direction) of the flow channel 101. By dividing the flow channel 101 into multiple sections with the one or more partition plates, a multi-layer flow channel is formed in the flow channel 101. This configuration increases the aspect ratio of the flow channel cross section of each layer of the multi-layer flow channel, making the flow two-dimensional, and rectifying the flow and stabilizing turbulence.

[0194] In this case, the representative length D is, for example, the length between the partition plates, or the length between one of the two side walls that face each other in the height H direction and form the flow path 101 and the partition plate closest to that side wall.

[0195] (5.4) Variation 4 The flow rate measurement unit 205 may convert the obtained flow rate Q into a flow rate at 0° C. and 1 atm (standard flow rate).

[0196] Furthermore, the flow rate measurement unit 205 may use the determined flow rate Q or standard flow rate to determine the flow rate of at least one gas other than water vapor that is contained in the mixed gas and is selected from the group consisting of a first gas (hydrocarbon), a second gas (oxygen), and a third gas (carbon dioxide). For example, the flow rate measurement unit 205 determines (measures) the flow rate of hydrocarbons by multiplying the determined flow rate Q or standard flow rate by the hydrocarbon concentration x1.

[0197] (5.5) Variation 5 The physical quantity measuring system 1 may include a plurality of temperature sensors 14. When the flow path main body 10 has a plurality of temperature sensors 14, the second signal processing unit 202 calculates the average value of the temperatures measured by the plurality of temperature sensors 14 as the temperature T of the mixed gas.

[0198] (5.6) Variation 6 The first ultrasonic transmitter / receiver 11 is arranged upstream and the second ultrasonic transmitter / receiver 12 is arranged downstream, facing each other, i.e., the arrangement direction of the first ultrasonic transmitter / receiver 11 and the second ultrasonic transmitter / receiver 12 intersects with the X direction, but this configuration is not limited to this.

[0199] The first ultrasonic transmitter / receiver 11 and the second ultrasonic transmitter / receiver 12 may be arranged along the X direction, but not intersect with the X direction.

[0200] In this case, the ultrasonic waves output from the first ultrasonic transmitter / receiver 11 are reflected within the flow path 101, and the reflected ultrasonic waves are input to the second ultrasonic transmitter / receiver 12. Furthermore, the ultrasonic waves output from the second ultrasonic transmitter / receiver 12 are reflected within the flow path 101, and the reflected ultrasonic waves are input to the first ultrasonic transmitter / receiver 11. That is, the path of the ultrasonic waves is V-shaped and crosses the flow of the mixed gas in the flow path 101. That is, in the sixth modification as well, the pair of ultrasonic transmitter / receivers 11, 12 are arranged so that the ultrasonic waves cross the flow of the mixed gas in the flow path 101.

[0201] (Other variations) The above embodiment is merely one of various embodiments of the present disclosure, and various modifications can be made to the above embodiment depending on the design and the like as long as the object of the present disclosure can be achieved.

[0202] Furthermore, functions similar to those of the physical quantity measurement system 1 may be embodied as a physical quantity measurement method, a computer program, or a non-transitory recording medium on which a program is recorded. A physical quantity measurement method according to one aspect is used in a physical quantity measurement system including a flow path 101 and a pair of ultrasonic transmitters and receivers 11 and 12. A mixed gas containing at least a third gas generated by combusting a first gas and a second gas in a combustor 3 flows through the flow path 101. The pair of ultrasonic transmitters and receivers 11 and 12 transmit and receive ultrasonic waves and are arranged so that the ultrasonic waves cross the flow of the mixed gas in the flow path 101. The physical quantity measurement method includes a concentration measurement step of measuring the concentration of gases contained in the mixed gas. When combustion is incomplete, the mixed gas contains unburned first and second gases. In the concentration measurement step, the concentrations of the first gas, the second gas, and the third gas are measured using the propagation time of the ultrasonic waves obtained by transmitting and receiving the ultrasonic waves at the pair of ultrasonic transmitters and receivers 11 and 12, the temperature of the mixed gas, and the equivalence ratio between the first gas and the second gas flowing into the combustor 3. A program according to one aspect is a program for causing a computer system to function as the above-described physical quantity measurement method.

[0203] The physical quantity measurement system 1 according to the present disclosure includes a computer system. The computer system is primarily composed of a processor and a memory as hardware. The processor executes a program stored in the memory of the computer system to realize the functions of the physical quantity measurement system 1 according to the present disclosure. The program may be pre-stored in the memory of the computer system, provided via a telecommunications line, or provided in a non-transitory recording medium such as a memory card, optical disk, or hard disk drive that is readable by the computer system. The processor of the computer system is composed of one or more electronic circuits including a semiconductor integrated circuit (IC) or a large-scale integrated circuit (LSI). The integrated circuits, such as ICs and LSIs, are referred to by different names depending on the degree of integration, and include integrated circuits called system LSIs, very large-scale integrations (VLSIs), and ultra-large-scale integrations (ULSIs). Furthermore, field-programmable gate arrays (FPGAs), which are programmable after the LSI is manufactured, or logic devices that allow the reconfiguration of internal connections or internal circuit partitions of the LSI, can also be used as processors. The electronic circuits may be integrated into one chip or distributed across multiple chips. The chips may be integrated into one device or distributed across multiple devices. The computer system referred to here includes a microcontroller having one or more processors and one or more memories. Therefore, the microcontroller is also composed of one or more electronic circuits including a semiconductor integrated circuit or a large-scale integrated circuit.

[0204] Furthermore, it is not essential for the physical quantity measurement system 1 that multiple functions in the physical quantity measurement system 1 are concentrated in one housing, and the components of the physical quantity measurement system 1 may be distributed across multiple housings. Furthermore, at least some of the functions of the physical quantity measurement system 1 may be realized by the cloud (cloud computing) or the like.

[0205] (summary) As described above, the physical quantity measuring system (1) of the first aspect includes a flow path (101), a pair of ultrasonic transmitter-receivers (11, 12), and a concentration measuring unit (204). A mixed gas containing at least a third gas generated by combusting a first gas and a second gas in a combustor (3) flows through the flow path (101). The pair of ultrasonic transmitter-receivers (11, 12) transmit and receive ultrasonic waves and are arranged so that the ultrasonic waves cross the flow of the mixed gas in the flow path (101). The concentration measuring unit (204) measures the concentrations of gases contained in the mixed gas. When combustion is incomplete, the mixed gas contains unburned first and second gases. The concentration measuring unit (204) measures the concentrations of the first gas, the second gas, and the third gas, respectively, using the propagation time of ultrasonic waves obtained by transmitting and receiving ultrasonic waves at the pair of ultrasonic transmitters and receivers (11, 12), the temperature of the mixed gas, and the equivalence ratio between the first gas and the second gas flowing into the combustor (3).

[0206] According to this aspect, by using the equivalence ratio, it is possible to take into account the excess gas, and therefore it is possible to measure the concentration of the gas contained in the mixed gas that flows out after combustion with high accuracy.

[0207] In the physical quantity measuring system (1) of the second aspect, the mixed gas further contains water vapor. The concentration measuring unit (204) measures the concentration of water vapor using the pressure of the mixed gas and the water vapor pressure, which is the pressure of the water vapor. The concentration measuring unit (204) measures the concentrations of the first gas, the second gas, and the third gas using the measured water vapor concentration, the propagation time of the ultrasonic waves, the temperature of the mixed gas, and the equivalence ratio.

[0208] According to this embodiment, even in high humidity, the concentration of the gas contained in the mixed gas that flows out after combustion can be measured with high accuracy.

[0209] In the physical quantity measuring system (1) of the third aspect, in the first or second aspect, the equivalence ratio is a value obtained by dividing the fuel-air ratio by the stoichiometric fuel-air ratio. The fuel-air ratio is a value obtained by dividing the first gas flowing into the combustor (3) by the second gas flowing into the combustor (3). When the equivalence ratio is greater than 1, the concentration measuring unit (204) measures the concentrations of the first gas, the second gas, and the third gas based on the ratio between the number of molecules of the first gas, which is the sum of the excess and unburned portions, the number of molecules of the unburned second gas, and the number of molecules of the generated third gas. When the equivalence ratio is less than 1, the concentration measuring unit (204) measures the concentrations of the first gas, the second gas, and the third gas based on the ratio between the number of molecules of the unburned first gas, the number of molecules of the second gas, which is the sum of the excess and unburned portions, and the number of molecules of the generated third gas. When the equivalence ratio is 1, the concentration measurement unit (204) measures the concentrations of the first gas, the second gas, and the third gas based on the ratio between the number of molecules of the unburned first gas, the number of molecules of the unburned second gas, and the number of molecules of the generated third gas.

[0210] According to this aspect, the concentration of the gas contained in the mixed gas that flows out after combustion can be measured with high accuracy based on the equivalence ratio.

[0211] The physical quantity measuring system (1) of a fourth aspect is any one of the first to third aspects, further including a flow rate measuring unit (205). The flow rate measuring unit (205) measures the flow rate of the mixed gas using the concentrations of the first gas, the second gas, and the third gas, the propagation time, the temperature of the mixed gas, and the pressure of the mixed gas.

[0212] According to this embodiment, the flow rate of the gas mixture that flows out after combustion can be measured with high accuracy.

[0213] The physical quantity measuring system (1) of a fifth aspect is the physical quantity measuring system (1) of any one of the first to fourth aspects, further including an output processing unit (206). The output processing unit (206) outputs the concentrations of the first gas and the second gas measured by the concentration measuring unit (204) to a control system (2) that controls the flow rates of the first gas and the second gas flowing into the combustor (3).

[0214] According to this embodiment, the concentrations of the first gas and the second gas measured by the concentration measuring unit 204 are output to the control system 2, whereby the control system 2 can perform feedback control, thereby enabling efficient combustion of the first gas and the second gas.

[0215] The physical quantity measuring system (1) of a sixth aspect is any one of the first to fifth aspects, further comprising a temperature sensor (14) that measures the temperature of the mixed gas.

[0216] According to this embodiment, the concentration of the gas contained in the mixed gas that flows out after combustion can be measured with high accuracy.

[0217] In the physical quantity measuring system (1) of the seventh aspect, in any one of the first to sixth aspects, the first gas is hydrocarbon, the second gas is oxygen, and the third gas is carbon dioxide.

[0218] According to this embodiment, the concentration of gas contained in a gas mixture generated by the combustion of hydrocarbon and oxygen can be measured with high accuracy.

[0219] An integrated system (1000) of an eighth aspect includes the physical quantity measuring system of any one of the first to seventh aspects and a combustor (3).

[0220] According to this aspect, by using the equivalence ratio, it is possible to take into account the excess gas, and therefore it is possible to measure the concentration of the gas contained in the mixed gas that flows out after combustion with high accuracy.

[0221] The integrated system (1000) of the ninth aspect is the eighth aspect, further comprising a control system (2). The control system (2) controls the flow rates of the first gas and the second gas flowing into the combustor (3).

[0222] According to this embodiment, the control system 2 can perform feedback control, and as a result, the first gas and the second gas can be combusted efficiently.

[0223] A tenth aspect of the physical quantity measuring method is used in a physical quantity measuring system (1) including a flow path (101) and a pair of ultrasonic transmitters and receivers (11, 12). A mixed gas containing at least a third gas generated by combusting a first gas and a second gas in a combustor (3) flows through the flow path (101). The pair of ultrasonic transmitters and receivers (11, 12) transmit and receive ultrasonic waves and are arranged so that the ultrasonic waves cross the flow of the mixed gas in the flow path (101). The physical quantity measuring method includes a concentration measuring step. In the concentration measuring step, the concentrations of gases contained in the mixed gas are measured. When combustion is incomplete, the mixed gas contains the first gas and the second gas that are unburned. In the concentration measurement step, the concentrations of the first gas, the second gas, and the third gas are measured using the propagation time of the ultrasonic waves obtained by transmitting and receiving the ultrasonic waves at the pair of ultrasonic transmitters and receivers (11, 12), the temperature of the mixed gas, and the equivalence ratio between the first gas and the second gas flowing into the combustor.

[0224] According to this aspect, by using the equivalence ratio, it is possible to take into account the excess gas, and therefore it is possible to measure the concentration of the gas contained in the mixed gas that flows out after combustion with high accuracy.

[0225] A program according to an eleventh aspect is a program for causing a computer system to execute the physical quantity measuring method according to the tenth aspect.

[0226] According to this aspect, by using the equivalence ratio, it is possible to take into account the excess gas, and therefore it is possible to measure the concentration of the gas contained in the mixed gas that flows out after combustion with high accuracy. [Explanation of symbols]

[0227] 1 Physical quantity measurement system 2. Control System 3 Combustor 11 Ultrasonic transmitter / receiver (first ultrasonic transmitter / receiver) 12 Ultrasonic transmitter / receiver (second ultrasonic transmitter / receiver) 14 Temperature Sensor 101 Flow path 204 Concentration measurement unit 205 Flow measurement unit 206 Output Processing Unit 1000 Integrated System

Claims

1. a flow path through which a mixed gas containing at least a third gas generated by combusting the first gas and the second gas in a combustor flows; a pair of ultrasonic transducers that transmit and receive ultrasonic waves and are arranged so that the ultrasonic waves cross the flow of the mixed gas in the flow channel; a concentration measuring unit that measures the concentration of a gas contained in the mixed gas; When combustion is incomplete, the mixed gas contains the first gas and the second gas that are unburned, The concentration measurement unit measuring the concentrations of the first gas, the second gas, and the third gas using a propagation time of the ultrasonic waves obtained by transmitting and receiving the ultrasonic waves between the pair of ultrasonic transmitter-receivers, a temperature of the mixed gas, and an equivalence ratio between the first gas and the second gas flowing into the combustor; Physical quantity measurement system.

2. the gas mixture further comprises water vapor; the concentration measurement unit measures the concentration of the water vapor using the pressure of the mixed gas and the water vapor pressure, which is the pressure of water vapor, and measures the concentrations of the first gas, the second gas, and the third gas using the measured water vapor concentration, the propagation time of the ultrasonic waves, the temperature of the mixed gas, and the equivalence ratio. The physical quantity measuring system according to claim 1 .

3. The equivalence ratio is a value obtained by dividing the fuel-air ratio by the stoichiometric fuel-air ratio, the fuel-air ratio is a value obtained by dividing the first gas flowing into the combustor by the second gas flowing into the combustor, The concentration measurement unit When the equivalence ratio is greater than 1, the concentrations of the first gas, the second gas, and the third gas are measured based on a ratio between the number of molecules of the first gas, which is the sum of the excess and unburned portion, the number of molecules of the unburned second gas, and the number of molecules of the generated third gas; When the equivalence ratio is less than 1, the concentrations of the first gas, the second gas, and the third gas are measured based on a ratio between the number of molecules of the unburned first gas, the number of molecules of the second gas obtained by adding the surplus and unburned gas, and the number of molecules of the generated third gas; When the equivalence ratio is 1, the concentrations of the first gas, the second gas, and the third gas are measured based on the ratio between the number of molecules of the unburned first gas, the number of molecules of the unburned second gas, and the number of molecules of the generated third gas. The physical quantity measuring system according to claim 1 .

4. a flow rate measuring unit configured to measure a flow rate of the mixed gas using the concentrations of the first gas, the second gas, and the third gas, the propagation time, the temperature of the mixed gas, and the pressure of the mixed gas. The physical quantity measuring system according to claim 1 .

5. an output processing unit that outputs the concentrations of the first gas and the second gas measured by the concentration measurement unit to a control system that controls the flow rates of the first gas and the second gas flowing into the combustor, The physical quantity measuring system according to claim 1 .

6. further comprising a temperature sensor that measures the temperature of the mixed gas; The physical quantity measuring system according to claim 1 .

7. the first gas is a hydrocarbon; the second gas is oxygen; The third gas is carbon dioxide. The physical quantity measuring system according to claim 1 .

8. a physical quantity measuring system according to any one of claims 1 to 7; The combustor. Integrated system.

9. a control system for controlling the flow rates of the first gas and the second gas flowing into the combustor, The integrated system of claim 8.

10. A physical quantity measuring method used in a physical quantity measuring system including: a flow path through which a mixed gas flows, the mixed gas including at least a third gas generated by burning a first gas and a second gas in a combustor; and a pair of ultrasonic transmitter-receivers that transmit and receive ultrasonic waves and are arranged so that the ultrasonic waves intersect a flow of the mixed gas in the flow path, a concentration measuring step of measuring the concentration of a gas contained in the mixed gas; When combustion is incomplete, the mixed gas contains the first gas and the second gas that are unburned, In the concentration measuring step, measuring the concentrations of the first gas, the second gas, and the third gas using a propagation time of the ultrasonic waves obtained by transmitting and receiving the ultrasonic waves between the pair of ultrasonic transmitter-receivers, a temperature of the mixed gas, and an equivalence ratio between the first gas and the second gas flowing into the combustor; Methods for measuring physical quantities.

11. A program for causing a computer system to execute the physical quantity measuring method according to claim 10.

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