Hydrogen-fueled aero-engine combustion chamber exhaust analysis test system, operation method and analysis test method

Abstract

This invention provides an exhaust gas analysis and testing system, operating method, and analysis and testing method for the combustion chamber of a hydrogen-powered aero-engine, relating to the field of engine emission testing technology. The system includes: a sampling and pretreatment pipeline assembly, an oxygen and conventional pollutant measurement assembly, a dual-path hydrogen measurement assembly, a control and safety assembly, and a data acquisition and processing assembly. The sampling and pretreatment pipeline assembly includes a sampling probe element and a pretreatment pipeline. The sampling probe element is connected to the pretreatment pipeline and is used to sample the exhaust gas from the combustion chamber. After sampling and pretreatment of the exhaust gas through the sampling and pretreatment pipeline assembly, the exhaust gas is transmitted to the oxygen and conventional pollutant measurement assembly and the dual-path hydrogen measurement assembly, respectively. After data measurement of the pretreated exhaust gas, the data acquisition and processing assembly records the signals of each analysis channel and stores and transmits the analysis data. The analysis and testing system provides full-process support from sample gas measurement to EI calculation.

Description

Technical Field

[0001] This invention relates to the field of engine emission testing technology, specifically to an exhaust gas analysis and testing system, operating method, and analysis and testing method for the combustion chamber of a hydrogen-powered aero-engine. Background Technology

[0002] With the increasing demand for green and low-carbon development of aero-engines, hydrogen fuel, due to its zero carbon emissions and high specific energy, is gradually becoming an important candidate fuel for aviation propulsion. Compared with the combustion products of traditional aviation kerosene, hydrogen combustion products have the following significant characteristics:

[0003] (1) High water content: Hydrogen combustion mainly produces water vapor, and the water content in the product can usually reach 20-30%, which is much higher than that in kerosene combustion exhaust. This makes condensation very easy to occur during sampling and analysis, causing measurement errors or even damaging the instrument;

[0004] (2) High diffusivity of hydrogen: The molecular diffusion coefficient of hydrogen is much higher than that of conventional gases such as CO2 and O2, making it easy to disperse and dilute in the sampling pipeline. At the same time, common polymer materials have high permeability to hydrogen, making it difficult to guarantee the accuracy of the measurement.

[0005] (3) Limitations of existing standards: Current emission testing standards such as those of the International Civil Aviation Organization (ICAO) are mainly geared towards kerosene combustion, and the testing system configuration usually includes NO X It has CO, CO2 and HC measurement modules, but lacks a dedicated design for hydrogen and high humidity environments.

[0006] Current laboratory tests for hydrogen combustion emissions mostly employ single-path hydrogen analyzers (such as thermal conductivity meters or mass spectrometers) combined with spectroscopic methods (such as Fourier transform infrared spectroscopy and tunable diode laser absorption spectroscopy) to measure water vapor content, and then calculate combustion efficiency and emission indices through a single conservation law. However, such experimental setups are usually temporary, with low system integration, lacking dedicated anti-condensation, anti-diffusion, and verification mechanisms, and failing to meet the long-term stability and standardization requirements for aero-engine emission testing. Furthermore, existing systems generally lack emission index (EI) calculation algorithms and data processing modules specifically for high-humidity hydrogen combustion conditions. Therefore, there is an urgent need for an integrated exhaust gas analysis system that combines testing and algorithmic functions to provide end-to-end support from sample gas measurement to EI calculation. Summary of the Invention

[0007] In view of this, the embodiments of this specification provide an exhaust gas analysis and testing system, operation method and analysis and testing method for the combustion chamber of a hydrogen-fired aero-engine, so as to achieve the purpose of supporting the entire process from sample gas measurement to EI calculation.

[0008] The embodiments in this specification provide the following technical solutions:

[0009] An exhaust gas analysis and testing system for the combustion chamber of a hydrogen-powered aircraft engine includes:

[0010] Sampling and pretreatment piping assembly, oxygen and conventional contaminant measurement assembly, dual-path hydrogen measurement assembly, control and safety assembly, and data acquisition and processing assembly;

[0011] The sampling and pretreatment tubing assembly includes a sampling probe element and a pretreatment tubing;

[0012] The sampling probe element is connected to the pretreatment pipeline and is used to sample the exhaust gas from the combustion chamber;

[0013] After sampling and pre-treatment of the exhaust gas through the sampling and pre-treatment pipeline assembly, the exhaust gas is transmitted to the oxygen and conventional pollutant measurement assembly and the dual-path hydrogen measurement assembly, respectively.

[0014] After measuring the pretreated exhaust gas using oxygen and conventional pollutant measurement components and dual-channel hydrogen measurement components, the data acquisition and processing components record the signals from each analysis channel and store and transmit the analytical data.

[0015] Furthermore, the sampling probe element includes a metal-lined sample gas tube and a water-cooled jacket that are sequentially fitted from the inside out, with thermal insulation ceramic disposed between the metal-lined sample gas tube and the water-cooled jacket.

[0016] The exhaust gas flows along the metal-lined sample gas pipe, and the cooling water flows along the water-cooled jacket. The flow direction of the cooling water is opposite to that of the exhaust gas.

[0017] Furthermore, the dual-path hydrogen measurement component includes a direct thermal and humidity measurement path and a dilution and dry measurement path connected in parallel.

[0018] The direct heat and humidity measurement pathway includes a first hydrogen analyzer connected via a heat tracing pipeline;

[0019] The dilution-dilution pathway includes a drying and dilution element and a second hydrogen analyzer.

[0020] Furthermore, the sampling and pretreatment piping assembly includes:

[0021] The pneumatic ball valve, back pressure valve, protection valve, pressure reducing valve, filter and diverter valve are connected in sequence through the heat tracing pipeline, and the flow meter and air compressor are connected in parallel with the heat tracing pipeline and connected in sequence through the ambient temperature pipeline.

[0022] The pneumatic ball valve is connected to the sampling probe element, the sampling probe element is connected to the ambient temperature pipeline, the ambient temperature pipeline is connected to the back pressure valve, and the diversion valve is connected to the oxygen and conventional pollutant measurement components and the dual-path hydrogen measurement components.

[0023] Furthermore, the oxygen and conventional pollutant measurement components include:

[0024] Analysis of branch paths, Analysis of branches and Analyze the branches;

[0025] The analytical circuit includes a condenser, a flow meter, and a non-dispersive infrared analyzer connected in sequence via ambient temperature piping;

[0026] The analytical circuit includes a condenser, a flow meter, and a paramagnetic analyzer connected in sequence via ambient temperature piping.

[0027] The analytical branch includes a protective filter, a flow meter, and an X-ray chemiluminescence analyzer, which are connected in sequence via a heat-traced pipeline.

[0028] A method for operating an analysis and testing system, which enables or disables the system, includes the following steps:

[0029] The heating element heating analysis and testing system controls the piping and critical components around the heating elements through control and safety components.

[0030] After sampling the exhaust gas from the combustion chamber of the hydrogen-fired aircraft engine using a sampling probe element, the exhaust gas enters the pretreatment pipeline.

[0031] The exhaust gas is condensed, filtered, depressurized and stabilized through a pretreatment pipeline. After treatment, the exhaust gas enters the oxygen and conventional pollutant measurement components and the dual-path hydrogen measurement components.

[0032] The concentration data of each component in the exhaust gas were measured using an oxygen and conventional pollutant measurement kit and a dual-path hydrogen measurement kit.

[0033] Concentration data is collected through data acquisition and processing components, and exhaust gas is analyzed and tested based on the concentration data;

[0034] The components and elements in the analysis and testing system are calibrated or corrected using control and safety components.

[0035] The control and safety components schedule the actuators of the heat tracing, pumps, valve switching, condensate drain, and dilution gas switching in the analysis and testing system, and monitor the anomalies of the analysis and testing system.

[0036] After the analysis and testing are completed, a shutdown command is issued through the control and safety components.

[0037] An analytical testing method for analyzing and testing the exhaust gas from the combustion chamber of a hydrogen-fired aircraft engine using an exhaust gas analysis and testing system includes the following steps:

[0038] The status of the direct heat and humidity measurement path and the dilution dry measurement path are acquired separately. Based on the status and the first data collected by the direct heat and humidity measurement path... Concentration data, dilution dry assay pathway acquisition second Concentration data, to obtain the final Concentration data;

[0039] Through respectively Analysis of branches, NO X The analysis branch and the CO / CO2 analysis branch simultaneously acquire component concentration data including timestamps. The component concentration data includes the final... Concentration data Concentration data Concentration data Concentration data Concentration data Concentration data and Concentration data;

[0040] Record and analyze the state variables of the test system, including dry / wet aperture, dilution ratio, converter efficiency, and sampling path selection.

[0041] Based on the component concentrations of each component in the combustion chamber exhaust gas, the state parameters of the analysis and testing system, and the port diameter information, the following calculations were performed: The number of moles and The number of moles;

[0042] Construct a formula for calculating the emission index, and then use the formula to calculate... The number of moles and The emission index is calculated from the number of moles.

[0043] Furthermore, the status of the direct heat and humidity measurement path and the dilution dry measurement path are acquired separately, and the first data collected by the direct heat and humidity measurement path is analyzed based on the status. Concentration data, dilution dry assay pathway acquisition second Concentration data, to obtain the final Concentration data, including:

[0044] Acquire the status information of the direct heat and humidity measurement path, which includes the sampling pipeline heating temperature, filter differential pressure, analyzer calibration status, and first data validity indicator.

[0045] Acquire the status information of the dilution dry test path, which includes the dilution ratio, dehumidifier dew point temperature, and second data validity indicator.

[0046] First sample was collected from the direct temperature and humidity measurement pathway. Concentration data;

[0047] Second sample collected from the dilution dry test pathway Concentration data, compared with the second dilution. Concentration data are restored and calculated to obtain corrected diluted dry weight. Concentration data;

[0048] Based on the status information of the direct heat and humidity measurement path, determine the first... Is the concentration data valid?

[0049] The second [test] is determined based on the status information of the dilution dry test pathway. Is the concentration data valid?

[0050] If the first The concentration data is valid, so the first one will be used. Concentration data as the final Concentration data;

[0051] If the first Concentration data invalid and second The concentration data is valid; the corrected data will be diluted and measured dry. Concentration data as the final Concentration data;

[0052] If the first Concentration data and second All concentration data are invalid; an error signal is output.

[0053] Furthermore, based on the component concentrations of each component in the combustion chamber exhaust gas, the state parameters of the analysis and testing system, and the aperture information, calculations were performed. The number of moles and The number of moles, including:

[0054] According to the general conservation equation Construct a system of equations for the mole number of each component. ,in, This represents the number of moles of intake air per mole of fuel. This represents the total number of moles of exhaust gas per unit mole of fuel. Let be the volume fraction of any component in the exhaust gas. This represents the volume fraction of any component in dry ambient air. For exhaust gas / After the converter Channel measured Volume fraction, for The number of moles, for The number of moles, for The number of moles, for The number of moles, for The number of moles, for The number of moles, for The number of moles, for The number of moles, The volumetric moisture content of ambient air. for / The efficiency of the converter;

[0055] Calculated using the aforementioned set of mole number equations The number of moles and The number of moles;

[0056] Calculated using the mole number equation system The number of moles and The number of moles.

[0057] Furthermore, the formula for calculating the emission index is as follows: ,in, for molecular weight, for atomic weight.

[0058] Compared with the prior art, the beneficial effects that at least one technical solution adopted in the embodiments of this specification can achieve include at least:

[0059] The analysis and testing system provides full-process support from sample gas measurement to EI calculation. Attached Figure Description

[0060] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0061] Figure 1 This is a structural diagram of the exhaust gas analysis and testing system for the combustion chamber of a hydrogen-fired aero-engine according to an embodiment of the present invention;

[0062] Figure 2 This is a schematic diagram of the sampling probe according to an embodiment of the present invention;

[0063] Figure 3 This is a schematic diagram of the sampling and preprocessing pipeline according to an embodiment of the present invention. Detailed Implementation

[0064] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0065] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0066] The analytical testing system provided in this invention comprises a sampling probe assembly, sampling and pretreatment tubing, a dual-path hydrogen measurement module, an oxygen and conventional pollutant measurement module, a control and safety unit, and a data processing and analysis module. The system structure and key designs are as follows:

[0067] 1. For example Figure 2 As shown, the sampling probe element includes:

[0068] a) Double-layer coaxial probe structure: the outer layer is a water-cooled jacket to resist high enthalpy gas flow and radiant heat, and the inner layer is a thin-walled metal liner sample tube (preferably 316L or nickel-based alloy).

[0069] b) Temperature field layout with internal heat and external cold: The inner lining is fully electrically heated and insulated, and the working wall temperature is preferably 150–180℃ (≥20K above the highest dew point); the outer water cooling layer is only used for structural cooling.

[0070] c) Thermal break / anti-cold bridge design: A ceramic heat insulation ring or equivalent heat insulation component is installed between the external water cooling and internal heating zones to avoid the formation of local cold spots at the tip / neck.

[0071] d) Multi-point temperature measurement: Install ≥3 thermocouples at the tip, neck, and root.

[0072] e) Size / throughput: The main sample gas channel of the liner is designed with a small diameter to reduce volume and retention (preferably inner diameter 2–4 mm); the length from the probe root to the first shunt point should be ≤1 m.

[0073] 2. For example Figure 3 As shown, the sampling and pretreatment pipeline includes the following functions:

[0074] a) Full-coverage heat tracing and insulation: The entire process of sampling arm, valves, connections, bypass and analysis branch is electrically heated and insulated, with the preferred temperature setting being 160℃ (not lower than 150℃).

[0075] b) High-speed bypass: A high-speed heating bypass is set from the probe outlet to the analysis branch point. The bypass has a small volume and a large flow rate. The bypass volume flow rate is ≥ 5–10 times the total flow rate of the analysis branch (preferably 50–100 SLPM) to achieve a step response of T90≤1s (based on system volume and flow rate matching calculation and acceptance).

[0076] c) Analysis branch: 1–5 SLPM (depending on analyzer requirements) is drawn from the branch point. Both the main line and the branch line use small-diameter metal tubing to reduce residence time and suppress diffusion.

[0077] d) Materials and sealing: Components in contact with the sample gas are preferably all-metal (316L, etc.); joints are metal-sealed, and the system helium leak detection index is ≤10-6 scc / s (or equivalent mass flow rate) to avoid H2 penetration and leakage.

[0078] e) Suction and flow control: The sampling system can be implemented through a bypass constant flow design, where the bypass flow can be monitored by a flow meter and adjusted by a back pressure valve; alternatively, a metal bellows pump or a high-temperature diaphragm pump can be used as the suction source, in conjunction with a mass flow controller or needle valve for fine adjustment, to maintain the stability of the total pressure and pressure drop of the sampling branch.

[0079] 3. Dual-channel hydrogen measurement component.

[0080] This invention sets up two parallel H2 measurement paths (direct heat and humidity measurement path and dilution dry measurement path) at the system level for redundant measurement and stability improvement in high humidity environments:

[0081] a) Direct heat and humidity measurement pathway: The sample gas enters the hydrogen analyzer (preferably a calorimeter or an equivalent H2 dedicated analyzer) under high temperature tracing conditions throughout the process, and outputs the H2 volume fraction in the "wet state aperture".

[0082] b) Dry test path after dilution: The sample gas and the dry dilution gas are mixed according to the set dilution ratio, and after terminal drying / condensation, they enter the hydrogen analyzer (preferably a calorimeter or an equivalent H2 dedicated analyzer), which outputs the H2 volume fraction in "dry state" (and records the dilution ratio).

[0083] c) Diameter and Interface: Both output channels are connected to the system data acquisition unit and record auxiliary parameters such as channel status, dilution ratio, temperature / pressure, etc., to provide conditions for subsequent data unification and quality control.

[0084] 4. Oxygen and conventional pollutant measurement components.

[0085] a) O2 measurement: Configure a paramagnetic oxygen analyzer (dry state aperture), with sampling line heating and aperture uniformity consistent with the H2 module.

[0086] b) NO X The current ICAO standard configuration is adopted, using a chemiluminescence analyzer (CLD) and maintaining consistency in dry-state diameter.

[0087] (c) CO / CO2: Although the content in hydrogen combustion products is extremely low, in order to ensure consistency with the ICAO framework and kerosene conditions, and as a means of monitoring abnormal conditions (such as incomplete combustion, carbon-blended fuel blending tests), this system retains the CO / CO2 measurement link and uses a non-dispersive infrared analyzer (NDIR).

[0088] c) Unified caliber management: The system provides dry / wet and diluted / undiluted caliber identification and switching mechanisms (valve groups and status variables) at the hardware level, and is uniformly recorded by the programmable logic controller (PLC) and the data acquisition system to ensure the consistency and traceability of data from different channels in terms of time, status and caliber.

[0089] 5. Control and safety components.

[0090] a) PLC and data acquisition: The PLC is responsible for the heat tracing circuit, pump, valve group and safety interlock; the data acquisition records the concentration, temperature, pressure and flow, valve position, diameter and status of each channel and timestamps it.

[0091] b) Safety and protection: hydrogen leak detection, forced ventilation of the analysis cabinet, inert gas purging, positive pressure / exhaust interlock, emergency shut-off valve, etc.; all electric heating / pump / valve have over-temperature / over-current / over-pressure protection and emergency stop logic.

[0092] 6. Data acquisition and processing components.

[0093] a) Unified data acquisition: Synchronously acquire H2 (dual-path), O2, NO X The data includes CO / CO2 concentration, temperature, pressure, flow rate, and other physical quantities for each channel, along with timestamps.

[0094] b) Aperture and dilution ratio management: Record status variables such as dry and wet aperture, dilution ratio, converter efficiency, and sampling path selection to form the raw input required for EI calculation;

[0095] c) Interlocking control with PLC: Schedule actuators such as heat tracing, pumps, valve groups, condensate drainage, and dilution gas switching, and trigger interlocks in abnormal states (abnormal temperature, leakage alarm, pressure exceeding limit);

[0096] d) Data consistency guarantee: Ensure data consistency for subsequent EI (NO) applications. x The consistency of all component data calculated in terms of scope, time, and state quantities provides complete data traceability capabilities;

[0097] e) Interface output: This is the EI(NO) output in the specific implementation. x The calculation method provides an input dataset, including component concentration, dry / wet basis states, dilution ratio, and other relevant physical state quantities, as well as the final EI (NO). x )value.

[0098] In the first embodiment of the present invention, the overall structure of the exhaust gas analysis system for the combustion chamber of a hydrogen-powered aircraft engine is as follows: Figure 1 As shown. The system includes: a combustion chamber, sampling probe element, flow valve, high-speed bypass, analysis branch, pretreatment system, analyzer assembly, PLC control unit, data acquisition and processing unit, and safety and protection unit. The workflow is as follows:

[0099] Step 1: Fuel and air mix and burn in the combustion chamber to form exhaust gas;

[0100] Step 2: The sampling probe element samples the exhaust gas from the combustion chamber, and the tail end is divided into two paths by the flow valve;

[0101] Step 3: The high-speed bypass is driven by the pump and works with the mass flow controller to maintain a high flow rate (50–100 SLPM) for rapid rinsing, and finally exhausts the gas.

[0102] Step 4: Maintain a low flow rate (1–5 SLPM) in the analysis branch and send it to the pretreatment system (condensation, filtration, pressure reduction, flow meter, etc.) before entering the analyzer assembly;

[0103] Step 5: The analyzer components include: H2 analyzer (dual-channel for direct heat and humidity measurement and dilution dry measurement), O2 paramagnetic analyzer, and NO... X Chemiluminescence analyzer, CO / CO2 non-dispersive infrared analyzer;

[0104] Step 6: The PLC control unit manages heat tracing, valves, pumps, and safety interlocks;

[0105] Step 7: The data acquisition and processing unit records the signals from each analysis channel and completes data storage, transmission, and real-time processing;

[0106] Step 8: The safety and protection unit is linked with the PLC and has protection functions such as hydrogen leak detection, forced ventilation, inert gas purging, positive pressure / exhaust interlock, and emergency shut-off.

[0107] In a second embodiment of the present invention, the sampling probe structure in the exhaust gas analysis system of a hydrogen-fired aero-engine combustion chamber is as follows: Figure 2 As shown. The probe adopts a double-layer structure with internal heating and external cooling: the outer layer is a water-cooled jacket (water inlet at the tail and water outlet at the front) to reduce the heat load; the inner layer is a small-diameter metal pipe (inner diameter 2–4 mm, preferably 2.5–3 mm), made of 316L or nickel-based alloy, with full-process heat tracing at 150–180℃; thermal insulation ceramic is installed between the inner and outer layers to prevent cold bridging; the tail of the probe has a metal sealed interface for connection with the flow valve.

[0108] In the third embodiment of the present invention, a sampling and pretreatment pipeline structure in a hydrogen-fired aircraft engine combustion chamber exhaust gas analysis system is shown, such as... Figure 3As shown in the diagram, this section is responsible for the gas transmission, diversion, purification, pressure regulation, and anti-condensation of the gas from the sampling probe to various gas analyzers, ensuring that the sample gas entering the analyzer is representative and stable.

[0109] (1) Sampling and preliminary adjustment.

[0110] Combustion chamber exhaust gas enters pneumatic ball valve via sampling probe to achieve opening and closing control of sampling gas path; main gas flow first enters flow meter and air compressor, and part of the gas is directly discharged through bypass (bypass venting) to maintain rapid response of system pressure and flow.

[0111] (2) Main road pretreatment.

[0112] The main gas passes sequentially through a back pressure valve (to maintain stable pipeline pressure), a protection valve (to prevent backflow), a pressure reducing valve (to adjust the gas pressure to a suitable range for analysis), and a filter (to remove particles and droplets); then it enters a diversion valve and is distributed to each analysis branch.

[0113] (3) Hydrogen analysis branch.

[0114] The hydrogen section adopts a dual-path structure: a) Direct heat and humidity measurement path: the gas passes through a protective filter and a flow meter in sequence, enters the thermal conductivity analyzer to measure the H2 concentration, and then is exhausted; b) Dilution and dry measurement path: an external dilution gas cylinder (passes through a protective filter, a pressure reducing valve, and a flow meter) is mixed with the sample gas, the mixed gas passes through a condenser to remove moisture, the condensate is discharged by a peristaltic pump, the gas then enters the thermal conductivity analyzer for measurement through a flow meter, and finally is exhausted.

[0115] (4) NO X Analyze the branch paths.

[0116] After passing through a protective filter and a flow meter, the gas directly enters the chemiluminescence analyzer to measure NO. X Concentration, exhaust emissions.

[0117] (5) O2 analysis branch.

[0118] The gas passes through a condenser to remove moisture (the condensate is discharged by a peristaltic pump), then through a flow meter into a paramagnetic oxygen analyzer to measure the O2 content, and finally the exhaust gas is emitted.

[0119] (6) CO / CO2 analysis branch.

[0120] The gas passes through a condenser to remove moisture (the condensate is discharged by a peristaltic pump), then through a flow meter into a non-dispersive infrared analyzer to measure the CO and CO2 content, before being emitted as exhaust gas.

[0121] (7) Heat tracing and ambient temperature pipelines.

[0122] The main sampling pipeline from the sampling probe to the shunt valve, as well as the H2 heat and humidity direct measurement branch and NO...X All branch lines are designed with heat tracing to maintain a temperature of 120–150℃ to prevent water vapor condensation and gas component loss. The dilution dry test path, O2 branch line, and CO / CO2 branch line are ambient temperature pipelines after the condenser to ensure that the gas entering each analyzer operates under stable conditions. The bypass vent, exhaust, and drain pipelines are auxiliary gas paths and are assumed to be at ambient temperature during operation, requiring no special heat tracing.

[0123] In a fourth embodiment of the present invention, an EI(NO) standard for hydrogen fuel cell aircraft engine exhaust conditions is provided. x ) Calculation method.

[0124] This embodiment illustrates the component concentration, physical state quantity, and aperture information (including dry / wet aperture, dilution ratio, converter efficiency, sampling path selection, and the concentration representation standard for each channel (dry / wet basis, diluted / undiluted, NO) provided by the testing system of this invention) based on the present invention. x (Whether the channel undergoes NO2 / NO conversion), constructing an EI (NO) suitable for hydrogen fuel cell aircraft engine exhaust conditions. x Calculation method:

[0125] 1. Basic Equation System.

[0126] Let the number of moles of each component after complete combustion of one mole of H2 be... Air input volume is The total number of moles of exhaust gas is , This refers to the volume fraction of the product components. The overall conservation equation for the volume fraction of gases in the air is as follows:

[0127] ;

[0128] The following 10 equations can be established, corresponding to the unknowns. , This can form a complete linear equation.

[0129] …………………………………………①

[0130] ……………………………………②

[0131] ……③

[0132] …………………………………④

[0133] ……………………………………………⑤

[0134] ……………………………………………⑥

[0135] …………………………………………⑦

[0136] …………………………………………⑧

[0137] ……………………………………………………⑨

[0138] ………………⑩

[0139] Components include , , , , , , and ,in, This represents the number of moles of intake air per mole of fuel. This represents the total number of moles of exhaust gas per unit mole of fuel. Let be the volume fraction of any component in the exhaust gas. This represents the volume fraction of any component in dry ambient air. For exhaust gas / After the converter Channel measured Volume fraction, for The number of moles, for The number of moles, for The number of moles, for The number of moles, for The number of moles, for The number of moles, for The number of moles, for The number of moles, The volumetric humidity of ambient air (the volume fraction of water vapor in moist air). for / The efficiency of the converter, used by Reverse calculation and True volume fraction ( ).

[0140] 2. EI (NO) x )calculate.

[0141] The expressions for the 10 unknowns are obtained by solving the simultaneous equations through elimination or by using MATLAB software. Then, according to the definitions... ,in, and Given the molecular weight of NO2 and the atomic weight of H, calculate the EI (NO2). x The value of ).

[0142] In the fifth embodiment of the present invention, an operation method and control logic for a hydrogen-fired aircraft engine combustion chamber exhaust gas analysis system are proposed, including the following steps:

[0143] Step 1: Power-on preparation.

[0144] The PLC controls the heating unit to raise the temperature to 150–180℃ to ensure that the sampling pipeline and key components are kept at a temperature higher than the water vapor dew point to prevent condensation; the system starts nitrogen purging to replace the sampling and pretreatment pipelines and remove residual gas from the sampling pipelines; the working status of components such as pumps, valves, and flow meters is checked to confirm that the safety interlocks are effective.

[0145] Step 2: Sampling phase.

[0146] The sampling probe samples the exhaust gas from the combustion chamber, and the sample gas enters the pipeline system through the probe tail; the high-speed bypass is activated to maintain a high flow rate of 50–100 SLPM, quickly refresh the sampling line, and reduce the residence time; the analysis branch maintains a low flow rate of 1–5 SLPM and enters the pretreatment unit.

[0147] Step 3: Preprocessing and Measurement.

[0148] The sample gas undergoes pretreatment processes including condensation, filtration, pressure reduction, and pressure stabilization to remove particles and some moisture, ensuring analytical stability. It then enters various gas analysis modules: H2 analysis (direct thermal and humidity measurement / dilution dry measurement), O2 paramagnetic analysis, NO... X Chemiluminescence analysis and CO / CO2 non-dispersive infrared analysis; PLC collects parameters such as concentration, flow rate, temperature, pressure, and dilution ratio of each channel in real time and transmits them to the data acquisition and processing system for storage and calculation.

[0149] Step 4: Calibration phase.

[0150] Switch the standard gas interface, and the PLC executes the zero-point and span correction program; each analyzer completes automatic calibration to ensure the accuracy and traceability of the data.

[0151] Step 5: Shutdown phase.

[0152] After the test is completed, the system switches to nitrogen purging to clean the sampling and pretreatment pipelines; the heat tracing unit, pump and valves are shut down in sequence; after the system cools down to a safe temperature, the PLC issues a shutdown command.

[0153] Step Six: Security and Protection Logic.

[0154] Throughout the operation, the PLC control unit is responsible for the logical linkage of components such as pumps and valves, and provides feedback control for key parameters such as temperature, pressure, and flow rate. All units are equipped with safety interlocks. When hydrogen leakage, over-temperature, or over-pressure is detected, the system automatically cuts off the sampling gas path and performs emergency purging. The analysis cabinet is equipped with forced ventilation and inert gas purging mechanisms to ensure the safety of the testing environment. The system has an emergency shut-off function to ensure rapid shutdown in case of emergencies.

[0155] Step 7: Data Acquisition and Processing.

[0156] Acquire collected data Solving equations ①-⑩ simultaneously, we obtain EI(NO) x The value of ).

[0157] In the sixth embodiment of the present invention, based on processing the raw data of two measurement pathways separately, evaluating their effectiveness, and selecting or fusing data based on state information, a reliable and accurate H2 concentration value is finally output. This provides a method for separately acquiring the states of the direct heat and humidity measurement pathway and the dilution dry measurement pathway, and based on the states, the first H2 concentration value collected by the direct heat and humidity measurement pathway... Concentration data, the second concentration data collected by the dilution dry test pathway Concentration data, to obtain the final The method for obtaining concentration data includes the following steps:

[0158] Step 1: Obtain the status information of the direct heat and humidity measurement path. The status information of the direct heat and humidity measurement path includes the sampling pipeline heating temperature, filter differential pressure, analyzer calibration status, and first data validity flag.

[0159] Step 2: Obtain the status information of the dilution dry test path, which includes the dilution ratio, dehumidifier dew point temperature, and second data validity indicator.

[0160] Step 3: Collect the first temperature and humidity data from the aforementioned direct temperature and humidity measurement path. Concentration data;

[0161] Step 4: Collect a second sample from the dilution dry test pathway. Concentration data, compared with the second dilution ratio Concentration data are restored and calculated to obtain corrected diluted dry weight. Concentration data;

[0162] Step 5: Determine the first [condition] based on the status information of the direct heat and humidity measurement path. Is the concentration data valid?

[0163] Step 6: Determine the second [method / condition] based on the status information of the dilution and dryness testing pathway. Is the concentration data valid?

[0164] Step 7: If the first If the concentration data is valid, the first H2 concentration data will be used as the final H2 concentration data. The concentration data is invalid and the second The concentration data is valid; the corrected dilution and dry testing will be performed. Concentration data as the final Concentration data, if the first Concentration data and the second All concentration data are invalid; an error signal is output.

[0165] Beneficial effects of the embodiments of the present invention:

[0166] By employing a double-layer coaxial probe with external cooling and internal heating, thermal tomography insulation, full-link high-temperature heat tracing, and a "drainage only at the end of the main branch" strategy, the potential for condensation at the front end is structurally eliminated, maintaining consistent diameter and protecting the analyzer. Compared to single-layer probes and conventional heat tracing in kerosene systems, this significantly reduces the risk of condensation under high dew point conditions and the resulting measurement deviations, improving system-level anti-condensation capabilities in high-humidity environments. By using a small-diameter main line + high-speed bypass, low volume / short residence / fast response (T90≤1s) is achieved. The all-metal gas path and metal seals work together to detect hydrogen leaks, suppressing H2 permeation and loss. Compared to conventional large-diameter, long-path, polymer-sealed kerosene systems, this... This invention significantly suppresses systematic errors caused by H2 dispersion / permeation, achieving high-fidelity sampling under conditions of high hydrogen diffusion. By paralleling two pathways—direct thermal and humid measurement and diluted dry measurement—it provides a redundant measurement condition and a unified hardware foundation at the system level, enhancing long-term operational stability and fault tolerance. Compared to existing "single-path H2" or laboratory-assembled solutions, it offers an engineered, integrable, and certifiable dual-path hardware framework, improving the engineering redundancy of dual-path H2 measurement. It comprehensively considers hydrogen safety (leakage monitoring, ventilation, purging, emergency stop, and interlocking), reducing maintenance frequency and life-cycle costs. Embodiments of this invention support hydrogen fuel EI (NOx). x High-precision calculation of data link integrity, enabling control over H2 (dual-path), O2, and NO. X A unified measurement link for CO / CO2, dry and wet basis management, dilution ratio recording, and full acquisition of temperature, pressure, and flow were established, and a connection was made with the traditional emission testing system EI (NO) for kerosene.x The calculations differ, and the EI (NOx) applicable to hydrogen fuels is different. x ) Calculation method.

[0167] The above description is merely a specific embodiment of the present invention and should not be construed as limiting the scope of the invention. Therefore, any substitution of equivalent components or equivalent changes and modifications made within the scope of protection of this patent should still fall within the scope of this patent. Furthermore, the technical features, technical features and technical solutions, and technical solutions in this invention can be freely combined and used.

Claims

1. A system for analyzing and testing exhaust gases from the combustion chamber of a hydrogen-powered aero-engine, characterized in that, include: Sampling and pretreatment piping assembly, oxygen and conventional contaminant measurement assembly, dual-path hydrogen measurement assembly, control and safety assembly, and data acquisition and processing assembly; The sampling and preprocessing pipeline assembly includes a sampling probe element and a preprocessing pipeline; The sampling probe element is connected to the pretreatment pipeline and is used to sample the exhaust gas from the combustion chamber. After the exhaust gas is sampled and pretreated by the sampling and pretreatment pipeline assembly, the exhaust gas is transmitted to the oxygen and conventional pollutant measurement assembly and the dual-path hydrogen measurement assembly, respectively. After measuring the data of the pretreated exhaust gas using the oxygen and conventional pollutant measurement component and the dual-path hydrogen measurement component, the data acquisition and processing component records the signals of each analysis channel and stores and transmits the analysis data. The sampling probe element includes a metal-lined sample gas tube and a water-cooled jacket, which are sequentially fitted from the inside to the outside. Thermal insulation ceramic is disposed between the metal-lined sample gas tube and the water-cooled jacket. The entire length of the inner lining is electrically heated and insulated. The inner diameter of the metal-lined sampling tube is 2 to 4 mm; The pretreatment pipeline includes a high-speed bypass and an analysis branch from the outlet of the sampling probe element to the analysis branch point. The pretreatment pipeline is used to provide full-process electric heat tracing and insulation for the sampling arm of the sampling probe element, all valves, the high-speed bypass, and the analysis branch. All analytical branches use small-diameter metal pipes.

2. The exhaust gas analysis and testing system according to claim 1, characterized in that, The exhaust gas flows along the metal-lined sample gas pipe, and the cooling water flows along the water-cooled jacket, with the flow direction of the cooling water opposite to that of the exhaust gas.

3. The exhaust gas analysis and testing system according to claim 1, characterized in that, The dual-path hydrogen measurement unit includes a direct thermal and humidity measurement path and a dilution and dry measurement path connected in parallel. The direct heat and humidity measurement pathway includes a first hydrogen analyzer connected via a heat tracing pipeline. The dilution-dilution pathway includes a drying and dilution element and a second hydrogen analyzer.

4. The exhaust gas analysis and testing system according to claim 1, characterized in that, The sampling and pretreatment pipeline assembly includes: A pneumatic ball valve, a back pressure valve, a protective valve, a pressure reducing valve, a filter, and a diverter valve are connected in sequence via a heat tracing pipeline, and a flow meter and an air compressor are connected in parallel with the heat tracing pipeline via a normal temperature pipeline. The pneumatic ball valve is connected to the sampling probe element, the sampling probe element is connected to the ambient temperature pipeline, the ambient temperature pipeline is connected to the back pressure valve, and the diversion valve is connected to the oxygen and conventional pollutant measurement component and the dual-path hydrogen measurement component.

5. The exhaust gas analysis and testing system according to claim 1, characterized in that, The oxygen and conventional pollutant measurement component includes: Analysis of branch paths, Analysis of branches and Analyze the branches; The The analytical circuit includes a condenser, a flow meter, and a non-dispersive infrared analyzer connected in sequence via ambient temperature piping; The The analytical circuit includes a condenser, a flow meter, and a paramagnetic analyzer connected in sequence via ambient temperature piping. The The analytical branch includes a protective filter, a flow meter, and a chemiluminescence analyzer connected in sequence via a heat tracing pipeline.

6. A method for operating an analysis and testing system, wherein the exhaust gas analysis and testing system according to any one of claims 1 to 5 is turned on or off by the method of operation, characterized in that, Includes the following steps: The control and safety components control the heating element to heat the piping and surrounding critical components of the analysis and testing system. After the exhaust gas from the combustion chamber of the hydrogen-fired aircraft engine is sampled using the sampling probe element, the exhaust gas enters the pretreatment pipeline. The exhaust gas is condensed, filtered, depressurized and stabilized through the pretreatment pipeline, and the treated exhaust gas enters the oxygen and conventional pollutant measurement component and the dual-path hydrogen measurement component. The concentration data of each component in the exhaust gas are measured using the oxygen and conventional pollutant measurement component and the dual-path hydrogen measurement component. The concentration data is collected by the data acquisition and processing component, and the exhaust gas is analyzed and tested based on the concentration data. The control and safety components are used to correct or calibrate the components and elements in the analysis and testing system. The control and safety components are used to schedule the actuators of the analysis and testing system, including heat tracing, pumps, valve switching, condensate drainage, and dilution gas switching, and to monitor any abnormalities in the analysis and testing system. After the analysis and testing are completed, a shutdown command is issued through the control and safety components.

7. An analytical testing method, comprising analyzing and testing the exhaust gas of a hydrogen-fired aircraft engine combustion chamber based on the exhaust gas analysis and testing system according to any one of claims 1 to 5, characterized in that, Includes the following steps: The states of the direct heat and humidity measurement path and the dilution dry measurement path are acquired respectively. Based on the states and the first data collected by the direct heat and humidity measurement path... Concentration data, the second concentration data collected by the dilution dry test pathway Concentration data, to obtain the final Concentration data; Through respectively Analysis of branch paths, The analysis branch and the CO / CO2 analysis branch simultaneously acquire component concentration data including timestamps, wherein the component concentration data includes the final... Concentration data Concentration data Concentration data Concentration data Concentration data Concentration data and Concentration data; Record and analyze the state variables of the test system, including dry / wet aperture, dilution ratio, converter efficiency, and sampling path selection; Based on the component concentrations of each component in the combustion chamber exhaust gas and the state quantity information of the analysis and testing system, the following calculations were performed: The number of moles and The number of moles; Construct a formula for calculating the emission index, and then use the formula based on the... The number of moles and the The emission index is calculated from the number of moles.

8. The analytical testing method according to claim 7, characterized in that, The states of the direct heat and humidity measurement path and the dilution dry measurement path are acquired respectively. Based on the states and the first data collected by the direct heat and humidity measurement path... Concentration data, the second concentration data collected by the dilution dry test pathway Concentration data, to obtain the final Concentration data, including: Acquire the status information of the direct heat and humidity measurement path, which includes the sampling pipeline heating temperature, filter differential pressure, analyzer calibration status, and first data validity flag. Acquire the status information of the dilution dry test path, which includes the dilution ratio, dehumidifier dew point temperature, and second data validity flag; The first sample was collected from the heat and humidity direct measurement path. Concentration data; A second sample was collected from the dilution interferometry pathway. Concentration data, compared with the second dilution ratio Concentration data are restored and calculated to obtain corrected diluted dry weight. Concentration data; Based on the status information of the heat and humidity direct measurement path, determine the first... Is the concentration data valid? The second determination is based on the status information of the dilution interference test path. Is the concentration data valid? If the first The concentration data is valid, so the first one... Concentration data as the final Concentration data; If the first The concentration data is invalid and the second The concentration data is valid; the corrected dilution and dry testing will be performed. Concentration data as the final Concentration data; If the first Concentration data and the second All concentration data are invalid; an error signal is output.

9. The analytical testing method according to claim 7, characterized in that, The results were calculated based on the component concentrations of each component in the combustion chamber exhaust gas, the state parameters of the analysis and testing system, and the aperture information. The number of moles and The number of moles, including: According to the general conservation equation Construct a system of equations for the mole number of each component. ,in, This represents the number of moles of intake air per mole of fuel. This represents the total number of moles of exhaust gas per unit mole of fuel. Let be the volume fraction of any component in the exhaust gas. This represents the volume fraction of any component in dry ambient air. For exhaust gas / After the converter Channel measured Volume fraction, for The number of moles, for The number of moles, for The number of moles, for The number of moles, for The number of moles, for The number of moles, for The number of moles, for The number of moles, The volumetric moisture content of ambient air. for / The efficiency of the converter; Calculated using the aforementioned set of mole number equations The number of moles and The number of moles.

10. The analytical testing method according to claim 7, characterized in that, The formula for calculating the emission index is as follows: ,in, for molecular weight, for atomic weight.

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