Gas generator outlet flow measurement device and method

Abstract

The present disclosure provides a gas generator outlet flow measurement device, comprising: a tail nozzle including an inner shell and an outer shell, the outer shell being sleeved outside the inner shell, a gas flow channel being defined between the inner shell and the outer shell and being suitable for accommodating gas passing through, the gas flow channel sequentially forming a straight section and an outlet section according to the flow direction of the gas; the straight section being configured as a tubular structure, one end of the straight section being fixedly connected with the outlet of the gas generator; the outlet section being arranged at the end of the straight section away from the gas generator, the outlet section being tapered along the radial direction of the straight section to form a throat, and expanding from the throat to form a gas outlet; and a detection mechanism being arranged in the straight section and being suitable for measuring the total temperature and total pressure of the outlet gas of the gas generator.

Description

Technical Field

[0001] At least one embodiment of this disclosure relates to the field of flow measurement, and more specifically, to a gas generator outlet flow measurement device and method. Background Technology

[0002] A gas turbine is a high-power, high-performance power machine that generates a high-temperature gaseous working fluid to drive a turbine mechanism to perform continuous work. A gas turbine typically consists of two main components: a gas generator and a power turbine. The gas generator produces high-temperature gas, which then enters the power turbine to drive the turbine impeller mechanism to perform work. In the development of such gas turbine products, the outlet flow rate of the gas generator is a key parameter affecting design performance; its design accuracy during the development process is crucial to whether the manufactured product can meet the design specifications.

[0003] In related technologies, the outlet flow rate of a gas generator is calculated by measuring the inlet air flow rate of a gas turbine. In order to ensure the accuracy of the inlet air flow rate measurement and to ensure that the inlet air flow rate measurement device does not cause high inlet losses, a large-volume and long flow tube device needs to be installed to measure the inlet air flow rate of the gas turbine.

[0004] Because flowmeter devices are only installed and used during gas turbine performance testing and not actually installed on the gas turbine in the industrial field, and because their installation can interfere with the airflow within the gas turbine, they can negatively impact the gas turbine's performance during testing. This can lead to a significant deviation between the gas turbine's performance during testing and its performance in industrial applications. Furthermore, the large size of the flowmeter device places additional demands on the space and supporting facilities of the gas turbine test bench, resulting in extra costs and requiring more space. These additional requirements increase the difficulty of testing gas turbine products. Summary of the Invention

[0005] To address at least one technical problem mentioned above and in other aspects in the prior art, this disclosure provides a gas generator outlet flow measurement device and method.

[0006] One embodiment of this disclosure provides a gas generator outlet flow measurement device, comprising: a tailpipe including an inner shell and an outer shell, the outer shell being sleeved on the outside of the inner shell, and a gas flow channel for accommodating gas passage defined between the inner shell and the outer shell, the gas flow channel sequentially forming a straight section and an outlet section according to the gas flow direction; the straight section being configured as a tubular structure, one end of the straight section being fixedly connected to the outlet of the gas generator; the outlet section being disposed at the end of the straight section away from the gas generator, the outlet section gradually narrowing radially along the straight section to form a throat, and expanding from the throat to form a gas outlet; and a detection mechanism disposed in the straight section, suitable for measuring the total temperature and total pressure of the outlet gas of the gas generator.

[0007] According to an embodiment of this disclosure, the straight section is provided with a plurality of measuring holes at uniform intervals along the circumference; the detection mechanism includes a plurality of total temperature sensors and a plurality of total pressure sensors, and each of the total temperature sensors and each of the total pressure sensors is alternately arranged in the measuring holes along the circumference.

[0008] According to an embodiment of this disclosure, one end of the inner shell and the outer shell connected to the gas generator extends in a direction parallel to the extension direction of the tail nozzle axis to form an annular straight section of a fixed diameter; the other end of the inner shell and the outer shell is uniformly tapered in a direction close to the axis of the tail nozzle to form the outlet section; wherein, the end of the outer shell away from the gas generator is configured to be arranged in an extension direction parallel to the axis of the tail nozzle to form the throat and the gas outlet formed by the expansion of the throat.

[0009] According to an embodiment of the present disclosure, in the portion of the outer shell and the inner shell that form the outlet section, the angle formed by the extending direction of the outer shell and the extending direction of the axis of the tail nozzle is greater than the angle formed by the extending direction of the inner shell and the extending direction of the axis of the tail nozzle.

[0010] Another aspect of the embodiments of this disclosure provides a method for measuring the outlet flow rate of a gas generator based on the aforementioned gas generator outlet flow rate measuring device, comprising: inputting the total temperature, total pressure, and thermodynamic parameters of the outlet gas of the gas generator and the fuel consumption of the gas generator; calculating the flow rate of the outlet gas based on the total temperature, total pressure, and thermodynamic parameters of the outlet gas; calculating the inlet air flow rate of the gas generator based on the flow rate of the outlet gas and the fuel consumption; iteratively calculating the inlet air flow rate of the gas generator until the inlet air flow rate of the gas generator meets a preset condition, outputting a target inlet air flow rate of the gas generator; and outputting the flow rate of the outlet gas corresponding to the target inlet air flow rate as a target outlet flow rate.

[0011] According to embodiments of this disclosure, the total temperature, total pressure, and thermodynamic parameters of the outlet gas input to the gas generator, and the fuel consumption of the gas generator, include: measuring and inputting the total temperature and total pressure of the outlet gas; determining the fuel consumption by the amount of fuel injected into the gas generator; and using the thermodynamic parameters of air as the initial thermodynamic parameters of the outlet gas.

[0012] According to embodiments of this disclosure, the calculation of the flow rate of the outlet gas based on the total temperature, total pressure, and thermodynamic parameters of the outlet gas includes: the thermodynamic parameters of the outlet gas include the specific heat ratio and gas constant of the outlet gas; the formula for calculating the flow rate of the outlet gas is:

[0013]

[0014] Where w is the flow rate of the outlet gas, k is the calibration coefficient, obtained based on the thermal expansion and contraction of the throat of the tailpipe, γ is the specific heat ratio of the outlet gas, and R g Let P be the gas constant of the outlet gas, T be the total pressure of the outlet gas, T be the total temperature of the outlet gas, and σ be the cross-sectional area of ​​the throat of the tailpipe perpendicular to the flow direction of the outlet gas.

[0015] According to embodiments of this disclosure, the calculation of the inlet air flow rate of the gas generator based on the outlet gas flow rate and the fuel consumption includes: obtaining the amount of gas drawn from the gas generator to other components; and calculating the inlet air flow rate based on the outlet gas flow rate, wherein the formula for calculating the inlet air flow rate is:

[0016] w 空气 =ww 燃料 -w 抽气 (2)

[0017] Among them, w 空气 w represents the inlet air flow rate of the aforementioned gas generator. 燃料 For the above fuel consumption, w 抽气 The above is the pumping volume.

[0018] According to embodiments of this disclosure, the iterative calculation of the inlet air flow rate of the gas generator includes: determining the chemical composition of the mixture formed by the complete combustion of the fuel and the reacted air based on the inlet air flow rate, the fuel consumption, and the chemical composition of the fuel; and calculating the thermodynamic parameters of the mixture based on the chemical composition of the mixture, including: calculating the isobaric specific heat C of the mixture based on the chemical composition of the mixture. p :

[0019]

[0020] The gas constant R of the above-mentioned gas mixture is calculated based on its chemical composition. g :

[0021]

[0022] Based on the isobaric specific heat C of the above-mentioned mixed gas p And the gas constant R of the above mixture g Calculate the specific heat ratio γ of the above mixture:

[0023]

[0024] Among them, C pi η is the specific heat at constant pressure of one of the gases in the above mixture. i M represents the mass percentage of a specific gas in the above mixture. i Let n be the molar mass of one of the gases in the above mixture, n be the number of pure chemical substances in the above mixture, and R be the universal gas constant.

[0025] The inlet air flow rate is iterated based on the specific heat ratio and gas constant of the above-mentioned mixed gas.

[0026] According to embodiments of this disclosure, the aforementioned preset conditions include:

[0027]

[0028] Among them, w j For the above-mentioned inlet air flow rate calculated in this iteration, w j-1 The above-mentioned inlet air flow rate was calculated in the previous iteration.

[0029] According to the gas generator outlet flow measurement device and method provided in this disclosure, the total temperature and total pressure of the outlet gas are measured by installing a tailpipe at the gas generator outlet. Then, based on the total temperature, total pressure, thermodynamic parameters of the outlet gas, and the fuel consumption of the gas generator, the inlet air flow rate of the gas generator is calculated and iteratively corrected until the inlet air flow rate meets preset conditions. The inlet air flow rate that meets the preset conditions is then used as the target inlet air flow rate output, and the target outlet flow rate corresponding to the target inlet air flow rate is determined. Since only a small tailpipe needs to be installed at the gas generator outlet, the airflow disturbance during gas turbine operation is minimal, avoiding the problem of significant deviations between gas turbine test performance and performance in industrial applications caused by installing flow pipe devices at the gas turbine inlet. Attached Figure Description

[0030] Figure 1This is a cross-sectional view of a tail nozzle according to an illustrative embodiment of the present disclosure;

[0031] Figure 2 Is it like this? Figure 1 The right view of the tail nozzle shown;

[0032] Figure 3 This is a flowchart of a gas generator outlet flow measurement method according to an illustrative embodiment of the present disclosure;

[0033] In the accompanying drawings, the meanings of the reference numerals are as follows:

[0034] 10-Tail nozzle;

[0035] 11-Inner shell;

[0036] 12-Outer shell;

[0037] 121 - Measuring hole;

[0038] 14-Support plate;

[0039] 141 - Vent hole;

[0040] 15-Plate;

[0041] 20 - Gas generator. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this disclosure clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0043] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0044] All terms used herein, including technical and scientific terms, have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0045] When using expressions such as "at least one of A, B, and C," the meaning should generally be interpreted according to the understanding of someone skilled in the art. For example, "a system having at least one of A, B, and C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C. Similarly, when using expressions such as "at least one of A, B, or C," the meaning should generally be interpreted according to the understanding of someone skilled in the art. For example, "a system having at least one of A, B, or C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C.

[0046] In measuring the performance of gas turbines, flow tube devices are often used to measure the inlet flow rate. However, because the flow tube device can cause some disturbance to the airflow during the test, it can affect the performance of the gas turbine. In actual industrial applications, flow tube devices are not installed on the gas turbine, resulting in a large deviation between the gas turbine performance measured by the inlet flow rate and the actual performance in actual applications.

[0047] Therefore, based on the aforementioned shortcomings of the existing technology, flow measurement is performed at the outlet of the gas generator. Since the outlet flow of the gas generator is equal to the outlet flow of the gas turbine, the above-mentioned problems can be effectively avoided by measuring the outlet flow of the gas generator. Therefore, there is an urgent need to propose a device and method for measuring the outlet flow of the gas generator.

[0048] In view of this, the present disclosure provides a gas generator outlet flow measurement device and method.

[0049] Figure 1 This is a cross-sectional view of a tailpipe according to an illustrative embodiment of the present disclosure.

[0050] like Figure 1 As shown, the gas generator outlet flow measurement device according to this disclosure includes a tailpipe 10 and a detection mechanism (not shown in the figure). The tailpipe 10 includes an inner shell 11 and an outer shell 12, with the outer shell 12 fitted over the inner shell 11. A gas flow channel suitable for accommodating gas passage is defined between the inner shell 11 and the outer shell 12. The gas flow channel sequentially forms a straight section and an outlet section according to the gas flow direction. The straight section is constructed as a tubular structure, with one end fixedly connected to the outlet of the gas generator 20. The outlet section is located at the end of the straight section away from the gas generator 20, and the outlet section gradually narrows radially along the straight section to form a throat, and expands from the throat to form a gas outlet. The detection mechanism is arranged in the straight section and is suitable for measuring the total temperature and total pressure of the outlet gas of the gas generator 20.

[0051] According to the above configuration, the high-temperature, high-pressure outlet gas generated by the gas generator 20 enters the tailpipe 10 through the outlet of the gas generator 20. The total temperature and pressure of the outlet gas are detected by a detection mechanism located in the straight section. Based on the total temperature and pressure of the outlet gas and its own thermodynamic parameters, the flow rate of the outlet gas from the gas generator 20 is calculated, thus obtaining the outlet flow rate of the gas generator 20. The outlet flow rate of the gas generator is the same as the outlet flow rate of the gas turbine, avoiding errors caused by installing a flow pipe device at the gas turbine inlet. In the tailpipe 10, the straight section is constructed as a tubular structure, allowing the outlet gas to flow smoothly within the straight section, which is beneficial for measuring the total temperature and pressure of the outlet gas. The outlet section is designed to first gradually narrow to a throat and then expand to form the gas outlet, effectively increasing the thrust of the outlet gas, enabling it to drive the turbine to do work, reducing additional performance losses, and ensuring the performance of the gas turbine.

[0052] According to an embodiment of this disclosure, the tail nozzle 10 is connected to the outlet flange at the rear end of the gas generator 20 via a flange structure and bolts.

[0053] In one illustrative embodiment, such as Figure 1 and Figure 2 As shown, a plurality of measuring holes 121 are evenly spaced along the circumference of the straight section. The detection mechanism includes a plurality of total temperature sensors and a plurality of total pressure sensors, with each total temperature sensor and each total pressure sensor alternately arranged in the measuring holes 121 along the circumference.

[0054] According to embodiments of this disclosure, the total temperature of the outlet gas can be taken as the geometric mean of the measurement results of multiple total temperature sensors, and the total pressure of the outlet gas can be taken as the geometric mean of the measurement results of multiple total pressure sensors.

[0055] In one illustrative embodiment, such as Figure 1 As shown, one end of the inner shell 11 and the outer shell 12 connected to the gas generator 20 extends in a direction parallel to the extension direction of the tail nozzle 10 axis, forming an annular straight section of a fixed diameter; the other end of the inner shell 11 and the outer shell 12 is uniformly tapered in a direction close to the axis of the tail nozzle 10 to form an outlet section; wherein, the end of the outer shell 12 away from the gas generator 20 is configured to be arranged in an extension direction parallel to the axis of the tail nozzle 10 to form a throat and a gas outlet formed by the expansion of the throat.

[0056] In one illustrative embodiment, such as Figure 1As shown, in the portion where the outer shell 12 and the inner shell 11 form the outlet section, the angle formed by the extension direction of the outer shell 12 and the extension direction of the axis of the tail nozzle 10 is greater than the angle formed by the extension direction of the inner shell 11 and the extension direction of the axis of the tail nozzle 10.

[0057] According to an embodiment of this disclosure, the angle formed by the extension direction of the outer shell 12 and the extension direction of the axis of the tail nozzle 10 is greater than 30°, and the angle formed by the extension direction of the inner shell 11 and the extension direction of the axis of the tail nozzle 10 is less than 25°.

[0058] In one illustrative embodiment, such as Figure 2 As shown, the tail nozzle 10 also includes a support plate 14, which is integrally formed with the inner shell 11 and surrounds the inner shell 11 to form an inner cavity, suitable for supporting and fixing the inner shell 11 radially from the tail nozzle 10.

[0059] According to embodiments of this disclosure, the support plate 14 has a plurality of ventilation holes 141 to balance the air pressure between the inner cavity and the external environment.

[0060] Figure 3 This is a flowchart of a gas generator outlet flow measurement method according to an illustrative embodiment of the present disclosure;

[0061] like Figure 3 As shown, the gas generator outlet flow measurement method provided in this disclosure includes:

[0062] Step S110: Input the total temperature, total pressure, thermodynamic parameters of the outlet gas of the gas generator 20, and the fuel consumption of the gas generator 20.

[0063] Step S120: Calculate the flow rate of the outlet gas based on the total temperature, total pressure and thermodynamic parameters of the outlet gas.

[0064] Step S130: Calculate the inlet air flow rate of the gas generator 20 based on the outlet gas flow rate and fuel consumption.

[0065] Step S140: Iteratively calculate the inlet air flow rate of the gas generator 20 until the inlet air flow rate of the gas generator 20 meets the preset conditions, and output the target inlet air flow rate of the gas generator 20.

[0066] Step S150: Output the outlet gas flow rate corresponding to the target inlet air flow rate as the target outlet flow rate.

[0067] Based on the above setup, since the thermodynamic parameters of the outlet gas are unknown, there is a significant difference between the initially input thermodynamic parameters of the outlet gas and the actual thermodynamic parameters of the outlet gas. Consequently, the calculated outlet gas flow rate differs significantly from the actual situation. However, since the fuel consumption is known, the inlet air flow rate can be calculated using the outlet gas flow rate and fuel consumption. The outlet gas flow rate can then be updated using the inlet air flow rate and fuel consumption. By continuously iterating the inlet air flow rate, a preset condition is achieved. Under this preset condition, the iteratively obtained inlet air flow rate is essentially consistent with the actual inlet air flow rate. Therefore, the outlet gas flow rate corresponding to the inlet air flow rate obtained in this iteration is also essentially consistent with the actual situation. The outlet gas flow rate of this iteration is used as the target outlet flow rate to complete the measurement of the outlet flow rate of the gas generator 20.

[0068] In one illustrative embodiment, step S110 includes:

[0069] Measure and input the total temperature and total pressure of the outlet gas. Determine the fuel consumption by the amount of fuel injected into the gas generator 20. Use the thermodynamic parameters of air as the initial thermodynamic parameters of the outlet gas.

[0070] Based on the above setup, since the thermodynamic parameters of air are known, they can be used as initial conditions in the iterative calculation to iterate the inlet air flow rate.

[0071] According to embodiments of this disclosure, the total temperature and total pressure of the outlet gas can be obtained by measuring the total temperature sensor and the total pressure sensor of the straight section of the tailpipe 10.

[0072] In one illustrative embodiment, step S120 includes:

[0073] The thermodynamic parameters of the outlet gas include the specific heat ratio and the gas constant.

[0074] The formula for calculating the outlet gas flow rate is:

[0075]

[0076] Where w is the flow rate of the outlet gas, k is the calibration coefficient, obtained based on the thermal expansion and contraction of the throat of the tail nozzle 10, γ is the specific heat ratio of the outlet gas, and R g σ is the gas constant of the outlet gas, P is the total pressure of the outlet gas, T is the total temperature of the outlet gas, and σ is the cross-sectional area of ​​the throat of the tail nozzle 10 perpendicular to the flow direction of the outlet gas.

[0077] Based on the above setup, in the initial calculations, the initial thermodynamic parameters of the outlet gas are the specific heat ratio γ of air and the gas constant R. g The total temperature T, total temperature P, and the cross-sectional area σ of the throat of the tail nozzle 10 perpendicular to the flow direction of the outlet gas, as well as the calibration coefficient k, are all known quantities. Therefore, the initial outlet gas flow rate can be calculated by equation (1) for subsequent iterative calculations.

[0078] In one illustrative embodiment, step S130 includes:

[0079] Obtain the amount of gas extracted from other components by the gas generator 20.

[0080] The inlet air flow rate is calculated based on the outlet gas flow rate. The formula for calculating the inlet air flow rate is as follows:

[0081] w 空气 =ww 燃料 -w 抽气 (8)

[0082] Among them, w 空气 The inlet air flow rate of the gas generator 20 is w 燃料 For fuel consumption, w 抽气 This refers to the air extraction volume.

[0083] In one illustrative embodiment, the iterative calculation of the inlet air flow rate of the gas generator 20 in step S140 includes:

[0084] The chemical composition of the mixture of fuel and air after complete combustion is determined based on the inlet air flow rate, fuel consumption, and the chemical composition of the fuel.

[0085] Based on the chemical composition of the gas mixture, calculate the thermodynamic parameters of the gas mixture, including:

[0086] Calculate the isobaric specific heat C of the gas mixture based on its chemical composition. p :

[0087]

[0088] Calculate the gas constant R of the gas mixture based on its chemical composition. g :

[0089]

[0090] Based on the isobaric specific heat C of the gas mixture p And the gas constant R of the mixture g Calculate the specific heat ratio γ of the gas mixture:

[0091]

[0092] Among them, C pi η is the specific heat at constant pressure of a certain gas in a gas mixture. i M represents the mass percentage of a particular gas in a gas mixture. i Let n be the molar mass of a certain gas in the mixture, n be the number of pure chemical substances in the mixture, and R be the universal gas constant.

[0093] Substitute the specific heat ratio and gas constant of the mixed gas into Equation (1), and substitute the updated outlet gas flow rate obtained in Equation (1) into Equation (2) to iterate the inlet air flow rate.

[0094] In one illustrative embodiment, the preset conditions in step S140 include:

[0095]

[0096] Among them, w j w represents the inlet air flow rate calculated in this iteration. j-1 This is the inlet air flow rate calculated in the previous iteration.

[0097] It should be noted that the gas generator outlet flow measurement method disclosed herein needs to be used when the total inlet pressure of the tail nozzle 10 is greater than 2 atmospheres; otherwise, if the flow channel at the throat of the tail nozzle 10 is not blocked, the measurement results of this method will be biased.

[0098] Based on the above technical solution, the gas generator outlet flow measurement device and method disclosed herein have one or more of the following beneficial effects:

[0099] 1. The gas generator outlet flow measurement device provided in this disclosure is small in size, will not cause additional performance loss to the gas generator, and reduces the deviation between the performance of the gas turbine on the test bench and the performance in the actual industrial site.

[0100] 2. The gas generator outlet flow measurement device provided in this disclosure has low requirements for the on-site support conditions of the test bench and can be directly installed on the gas generator. In addition, the gas generator outlet flow measurement device provided in this disclosure can also be used as the exhaust device of the gas generator, which reduces the modification cost of the gas generator test bench for flow measurement.

[0101] It should also be noted that the directional terms mentioned in the embodiments, such as "up," "down," "front," "back," "left," and "right," are only for reference to the directions in the accompanying drawings and are not intended to limit the scope of protection of this disclosure. Throughout the drawings, the same elements are represented by the same or similar reference numerals. Conventional structures or constructions will be omitted where they may cause confusion in understanding this disclosure.

[0102] The embodiments of this disclosure have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of this disclosure. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. The scope of this disclosure is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of this disclosure, and all such substitutions and modifications should fall within the scope of this disclosure.

Claims

1. A method for measuring the outlet flow rate of a gas generator, characterized in that, Based on a gas generator outlet flow measurement device, the measurement device includes: The tail nozzle includes an inner shell and an outer shell, the outer shell being fitted over the outside of the inner shell, and a gas flow channel is defined between the inner shell and the outer shell for accommodating gas flow, the gas flow channel being formed sequentially into a straight section and an outlet section according to the gas flow direction; The straight section is constructed as a tubular structure, and one end of the straight section is fixedly connected to the outlet of the gas generator. The outlet section is located at the end of the straight section away from the gas generator, the outlet section gradually narrows radially along the straight section to form a throat, and expands from the throat to form a gas outlet; and The testing mechanism, arranged in the straight section, is suitable for measuring the total temperature and total pressure of the outlet gas of the gas generator. The measurement method includes: The total temperature, total pressure, and thermodynamic parameters of the outlet gas of the gas generator are input, as well as the fuel consumption of the gas generator. The flow rate of the outlet gas is calculated based on the total temperature, total pressure, and thermodynamic parameters of the outlet gas. The inlet air flow rate of the gas generator is calculated based on the outlet gas flow rate and the fuel consumption, wherein, The thermodynamic parameters of the outlet gas include the specific heat ratio and gas constant of the outlet gas; The formula for calculating the flow rate of the outlet gas is: Where w is the flow rate of the outlet gas, k is a calibration coefficient obtained based on the thermal expansion and contraction of the throat of the tailpipe, γ is the specific heat ratio of the outlet gas, and R g Let P be the gas constant of the outlet gas, P be the total pressure of the outlet gas, and T be the total temperature of the outlet gas. The cross-sectional area of ​​the throat of the tail nozzle perpendicular to the flow direction of the outlet gas; The inlet air flow rate of the gas generator is iteratively calculated until the inlet air flow rate of the gas generator meets the preset conditions, and the target inlet air flow rate of the gas generator is output. The output flow rate of the outlet gas corresponding to the target inlet air flow rate is the target outlet flow rate.

2. The method for measuring the outlet flow rate of a gas generator according to claim 1, characterized in that, The straight section is provided with multiple measuring holes at uniform intervals along the circumference; The detection mechanism includes multiple total temperature sensors and multiple total pressure sensors, with each total temperature sensor and each total pressure sensor alternately arranged circumferentially in the measuring hole.

3. The method for measuring the outlet flow rate of a gas generator according to claim 1, characterized in that, The inner shell and the outer shell extend in a direction parallel to the extension direction of the axis of the tail nozzle, forming a straight section with a fixed diameter and an annular shape. The inner shell and the outer shell are uniformly tapered at the other end along the axis close to the tail nozzle to form the outlet section. The end of the housing away from the gas generator is configured to extend in a direction parallel to the axis of the tailpipe to form the throat and the gas outlet formed by the expansion of the throat.

4. The method for measuring the outlet flow rate of a gas generator according to claim 3, characterized in that, In the portion of the outer shell and the inner shell that form the outlet section, the angle formed by the extending direction of the outer shell and the extending direction of the axis of the tail nozzle is greater than the angle formed by the extending direction of the inner shell and the extending direction of the axis of the tail nozzle.

5. The method for measuring the outlet flow rate of a gas generator according to claim 1, characterized in that, The total temperature, total pressure, and thermodynamic parameters of the outlet gas of the input gas generator, and the fuel consumption of the gas generator, include: Measure and input the total temperature and total pressure of the outlet gas; The fuel consumption is determined by the amount of fuel injected into the gas generator; The thermodynamic parameters of air are used as the initial thermodynamic parameters of the outlet gas.

6. The method for measuring the outlet flow rate of a gas generator according to claim 1, characterized in that, The calculation of the inlet air flow rate of the gas generator based on the outlet gas flow rate and the fuel consumption includes: Obtain the amount of gas extracted by the gas generator to other components; The inlet air flow rate is calculated based on the outlet gas flow rate, and the formula for calculating the inlet air flow rate is as follows: Among them, w 空气 w is the inlet air flow rate of the gas generator. 燃料 For the fuel consumption, w 抽气 The pumping volume is [value].

7. The method for measuring the outlet flow rate of a gas generator according to claim 6, characterized in that, The iterative calculation of the inlet air flow rate of the gas generator includes: The chemical composition of the mixture of the fuel after complete combustion and the reacted air is determined based on the inlet air flow rate, the fuel consumption, and the chemical composition of the fuel. Based on the chemical composition of the gas mixture, calculate the thermodynamic parameters of the gas mixture, including: The isobaric specific heat C of the gas mixture is calculated based on its chemical composition. p : The gas constant R of the gas mixture is calculated based on its chemical composition. g : Based on the isobaric specific heat C of the mixture p and the gas constant R of the mixture g Calculate the specific heat ratio γ of the gas mixture: Among them, C pi η is the specific heat at constant pressure of one of the gases in the mixture. i M represents the mass percentage of a particular gas in the gas mixture. i Let n be the molar mass of a certain gas in the mixture, n be the number of pure chemical substances in the mixture, and R be the universal gas constant. The inlet air flow rate is iterated based on the specific heat ratio and gas constant of the mixture.

8. The method for measuring the outlet flow rate of a gas generator according to any one of claims 1-7, characterized in that, The preset conditions include: Among them, w j w is the inlet air flow rate calculated in this iteration. j-1 The inlet air flow rate is the one calculated in the previous iteration.

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