A mass spectrometry ionization source for online detection of combustion gas components at the outlet of an aircraft engine combustion chamber

Abstract

The present invention belongs to the technical field of mass spectrometry ionization sources and provides a mass spectrometry ionization source for online detection of fuel gas components at the outlet of an aircraft engine combustion chamber. The mass spectrometry ionization source solves the problem that existing ionization sources are difficult to apply to field tests for measuring component concentrations at the outlet of a real aircraft engine combustion chamber. The mass spectrometry ionization source comprises an ionization source cavity and a radio frequency windowless discharge lamp. A flat plate electrode, a cone electrode, a lamp holder electrode, a direct current transmission electrode, a radio frequency transmission electrode, and a differential electrode are sequentially arranged inside the ionization source cavity along an axial direction. A discharge gas inlet is provided on the ionization source cavity. One end of the radio frequency windowless discharge lamp is connected to the discharge gas inlet, and the other end extends into the interior of the lamp holder electrode. The cone electrode allows fuel gas to be sampled in the form of a molecular beam, thereby ensuring efficient transmission of stable components and active components in the fuel gas. Efficient transmission of ions is achieved by combining the direct current transmission electrode with the radio frequency transmission electrode, thereby achieving full-spectrum online analysis of fuel gas components at the outlet of the aircraft engine combustion chamber.

Description

Technical Field

[0001] The invention belongs to the technical field of mass spectrometry ionization sources, and in particular relates to a mass spectrometry ionization source for online detection of fuel gas components at an outlet of an aircraft engine combustion chamber. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] As one of the key indicators of aeroengine combustion chamber performance, the flow field parameters at the combustion chamber outlet directly reflect the quality of combustion. Due to the increased thrust-to-weight ratio of modern aeroengine combustion chambers, the outlet flow field is characterized by high temperature, high pressure, and high turbulence. Advanced combustion chamber design requirements increase the combustor outlet temperature and the head intake volume, resulting in a sharp decrease in the amount of mixed air, and the outlet flow field environment becomes even more severe. To achieve breakthroughs in the design of next-generation, high-performance aeroengine combustion chambers, it is necessary to be able to measure and calculate combustion performance parameters such as combustion efficiency, fuel-to-air ratio, and pollutant emissions. Therefore, high-precision measurement and analysis of the component concentrations at the combustion chamber outlet is essential.

[0004] Aircraft engines use jet fuel as fuel. While the concentrations of combustion gas components vary under different operating conditions, all engines produce a variety of combustion products, including O2, CO, CO2, H2O, NOx, and UHC. The physical and chemical properties of these gas components vary significantly, necessitating the selection of appropriate detection technologies. Gas analysis continuously measures the composition of the combustion chamber outlet gas, directly measuring its concentration and indirectly calculating performance parameters such as the fuel-to-gas ratio, combustion efficiency, and gas temperature.

[0005] The current assembled gas analysis cabinets, which detect UHC, CO / CO2, O2, and NOx in gas, are large and difficult to maintain. Furthermore, existing gas analysis systems do not adequately adhere to standards. For example, pipeline insulation does not meet standard requirements, the conversion efficiency of the NOx analyzer converter does not meet standard requirements, and gas composition analyzers are not calibrated and inspected according to standard requirements.

[0006] Mass spectrometry uses an ionization source to ionize a gas sample to produce gas-phase ions. A mass analyzer is then used to separate and analyze these ions based on their mass-to-charge ratio. This allows for the detection of gas components at the outlet of an aircraft engine combustion chamber. The ionization source is one of the core components of a mass spectrometer and is closely linked to its detection performance.

[0007] The current mass spectrometry ionization sources have the following technical defects:

[0008] 1. Current mass spectrometry ionization sources have difficulty detecting samples with high ionization energies. For example, the invention with publication number "CN102479661B," titled "Combined ionization source of vacuum ultraviolet photoionization and chemical ionization for mass spectrometry analysis," can detect acetonitrile (12.2 eV), chloroform (11.37 eV), and acetic acid (11.65 eV), which have ionization energies higher than the energy of vacuum ultraviolet light (10.6 eV). However, this ionization source is not suitable for detecting CO and CO2 in aircraft engine fuel gas, which have higher ionization energies.

[0009] 2. Current research uses a molecular beam ionization source combined with a synchrotron radiation source to conduct combustion kinetics experiments and model studies on single-chain aromatic hydrocarbons, aromatic hydrocarbons, butanol, cyclohexane and its monoalkyl derivatives, and typical alkanes and cycloalkanes. This allows for efficient ionization of components at the outlet of aircraft engine combustion chambers. However, given the high cost of synchrotron radiation sources and the stringent measurement environment requirements, current work focuses primarily on studying the composition of enol combustion intermediates and some important free radicals in low-pressure, laminar premixed flames under laboratory conditions, which falls far short of the testing requirements under actual engine operating conditions.

[0010] 3. An ionization source combining hard electron ionization and soft single-photon ionization has been developed and studied on mineral diesel samples. Hard electron ionization, in which electrons with a kinetic energy of 70 eV are emitted from a luminescent tungsten filament, can ionize inorganic components with high ionization energies. However, this also produces fragment ions of organic compounds with lower ionization energies, affecting subsequent spectral analysis. Furthermore, hard electron ionization requires the use of long capillaries, which limits the sample volume and, therefore, cannot detect highly reactive species such as free radicals. Soft single-photon ionization, using 9.8 eV soft photons, enables analysis of organic components. Detection also requires complex timing control to switch between hard electron ionization and soft single-photon ionization, resulting in long single-shot detection times and low efficiency. Summary of the Invention

[0011] In order to solve at least one technical problem existing in the above-mentioned background technology, the present invention provides a mass spectrometry ionization source for online detection of the composition of the gas at the outlet of the aircraft engine combustion chamber. It injects samples in the form of a molecular beam, ensuring the efficient transmission of stable components and active components in the gas, and realizes efficient transmission of ions by combining a DC transmission electrode with a radio frequency transmission electrode, which can realize full-spectrum online analysis of the composition of the gas at the outlet of the aircraft engine combustion chamber.

[0012] In order to achieve the above object, the present invention adopts the following technical solutions:

[0013] A mass spectrometry ionization source for online detection of combustion gas composition at the outlet of an aircraft engine combustion chamber comprises an ionization source cavity and a radio frequency windowless discharge lamp. A flat plate electrode, a cone electrode, a lamp cap electrode, a DC transmission electrode, a radio frequency transmission electrode, and a differential electrode are sequentially arranged inside the ionization source cavity along an axial direction. The multiple electrodes are mutually parallel and coaxially arranged with a central through hole.

[0014] A discharge gas inlet is provided on the ionization source cavity, one end of the radio frequency windowless discharge lamp is connected to the discharge gas inlet, and the other end extends into the interior of the lamp holder electrode;

[0015] The flat electrode, cone electrode, lamp cap electrode, DC transmission electrode, radio frequency transmission electrode and differential electrode are sequentially loaded with different voltages in descending order of absolute voltage value, forming an ion transmission channel in the axial direction.

[0016] As an embodiment, the flat electrode, the conical hole electrode and the differential electrode are all plate-type electrodes with a conical protrusion at the center, and the tip of the cone is processed with a through hole for ion transmission along the transverse direction;

[0017] The lamp holder electrode is a cylindrical structure with a through hole in the center;

[0018] The DC transmission electrode and the RF transmission electrode are both plate-type structures with a central opening.

[0019] As an embodiment, the through hole diameter of the flat electrode is 0.3-0.5 mm, the through hole diameter of the conical hole electrode is 1-2 mm, the through hole diameter of the differential electrode is 0.6-1.5 mm, and the conical hole angle is 40-50°.

[0020] As an embodiment, the ionization source further includes a discharge gas storage and a mass flow controller, the air inlet end of the RF windowless discharge lamp is connected to the air outlet end of the mass flow controller, and the air inlet end of the mass flow controller is connected to the discharge gas storage.

[0021] As an embodiment, the discharge gas stored in the discharge gas storage device is helium, neon or argon.

[0022] As an embodiment, the area between the flat electrode and the conical electrode constitutes a gas buffer zone; the area between the conical electrode and the DC transmission electrode constitutes a gas component ionization zone.

[0023] As an embodiment, the ionization source further includes a vacuum pump group, the vacuum pump group includes an oil pump and a dry pump, the oil pump is connected to the gas buffer zone, and the dry pump is connected to the gas component ionization zone.

[0024] As an embodiment, the discharge tube in the radio frequency windowless discharge lamp is made of quartz, a high-frequency coil is wound around the discharge tube, a high-frequency voltage is applied to the high-frequency coil, and the discharge gas discharges in the discharge tube to generate photons and metastable atoms / molecules.

[0025] As an embodiment, the RF transmission electrode adopts a segmented quadrupole, which is composed of multiple segmented electrode rings. The electrode rings are fixed on four insulating rods placed at equal intervals, and each electrode ring is isolated by insulating rings of the same size. The electrode ring of each pole is applied with a DC voltage through a voltage-dividing resistor to form a DC electric field along the axis, and at the same time, capacitors of the same capacitance are connected to apply RF voltage.

[0026] As an embodiment, an ion outlet is provided on the differential electrode, and the ion outlet is connected to a mass spectrometer.

[0027] The beneficial effects of the present invention are:

[0028] 1. The conical electrode of the present invention allows the gas to be sampled in the form of a molecular beam, ensuring the efficient transmission of stable and active components in the gas. By combining the DC transmission electrode with the RF transmission electrode, efficient ion transmission is achieved, enabling full-spectrum online analysis of the gas composition at the outlet of the aircraft engine combustion chamber.

[0029] 2. The present invention changes the sampling mode of online mass spectrometry from the commonly used capillary sampling to molecular beam sampling. The molecular beam sampling form can prevent the active components in the high-temperature fuel gas from further reaction. Therefore, it can not only detect stable inorganic components in the fuel gas, but also realize the detection of highly reactive species such as various free radicals and intermediates. It can be applied to the detection of fuel gas at the outlet of the real aircraft engine combustion chamber, expanding the application range of the mass spectrometer.

[0030] 3. The present invention uses a radio frequency windowless lamp as its light source. This windowless design is unaffected by the harsh environment of aircraft engine combustion chambers, eliminating window contamination and enabling long-term use. Using helium as the discharge gas generates photons with energies of 21.2 eV and metastable helium atoms / molecules. This generates a dual ionization process within the ionization source: VUV photoionization and Penning ionization. This enables full-spectrum online analysis of both inorganic and organic components in the combustion gas exiting the aircraft engine combustion chamber.

[0031] 4. The windowless radio frequency lamp of the present invention is relatively small in size and can be placed inside the ionization source cavity, thereby integrating the ionization source and obtaining a higher luminous flux.

[0032] Advantages of additional aspects of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0034] Figure 1 This is a schematic diagram of the structure of an online mass spectrometry ionization source for combustion chamber outlet gas of an aircraft engine provided by an embodiment of the present invention;

[0035] Figure 2 This is a mass spectrum of CO detected by an online mass spectrometry ionization source for combustion gas at the outlet of an aircraft engine combustion chamber provided by an embodiment of the present invention;

[0036] Figure 3 This is a mass spectrum of CO2 detected by an online mass spectrometry ionization source for combustion gas at the outlet of an aircraft engine combustion chamber provided by an embodiment of the present invention;

[0037] Figure 4 This is a mass spectrum of H2O detected by an online mass spectrometry ionization source for combustion gas at the outlet of an aircraft engine combustion chamber provided by an embodiment of the present invention;

[0038] Figure 5 This is a mass spectrum of NO detected by an online mass spectrometry ionization source for combustion gas at the outlet of an aircraft engine combustion chamber provided by an embodiment of the present invention;

[0039] Figure 6 This is a mass spectrum of NO2 detected by an online mass spectrometry ionization source for combustion gas at the outlet of an aircraft engine combustion chamber provided by an embodiment of the present invention;

[0040] Figure 7 This is the mass spectrum of O2 detected by online mass spectrometry ionization source of the combustion chamber outlet gas of an aircraft engine provided by an embodiment of the present invention.

[0041] Figure 8 This is a mass spectrum of UHC detected by an online mass spectrometry ionization source of the combustion chamber outlet gas of an aircraft engine provided by an embodiment of the present invention.

[0042] Among them, 1. Flat electrode; 2. Conical hole electrode; 3. Lamp holder electrode; 4. DC transmission electrode; 5. RF transmission electrode; 6. Differential electrode; 7. Oil pump; 8. RF windowless discharge lamp; 9. Mass flow controller 9; 10. Discharge gas storage; 11. Dry pump. DETAILED DESCRIPTION

[0043] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0044] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention belongs.

[0045] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0046] In the present invention, terms such as "connected" and "connection" should be interpreted broadly to mean a fixed connection, an integral connection, or a detachable connection; a direct connection or an indirect connection through an intermediary. Relevant researchers or technicians in this field may determine the specific meanings of these terms in the present invention based on specific circumstances, and they should not be construed as limitations on the present invention.

[0047] As described in the background, the current harsh flow environment at the combustor exit of aircraft engines necessitates the development of novel measurement technologies to accurately measure component concentrations at the combustor exit. Existing gas analysis technologies rely on multiple imported instruments to detect gas component concentrations, making it difficult to trace the source of errors between different technologies. While online mass spectrometry ionization sources based on synchrotron radiation and ionization sources combining hard electron ionization and soft single-photon ionization can measure gas component concentrations at the combustor exit of aircraft engines, these technologies are difficult to apply to field tests of actual aircraft engine combustor exit component concentration measurements. In order to solve the above technical problems, the present invention proposes a mass spectrometry ionization source for online detection of the composition of the gas at the outlet of an aircraft engine combustion chamber, comprising an ionization source cavity and a radio frequency windowless discharge lamp. A flat electrode, a conical hole electrode, a lamp holder electrode, a DC transmission electrode, a radio frequency transmission electrode and a differential electrode are arranged in sequence along the axial direction inside the ionization source cavity. A discharge gas inlet is provided on the ionization source cavity. One end of the radio frequency windowless discharge lamp is connected to the discharge gas inlet, and the other end extends into the interior of the lamp holder electrode; the conical hole electrode allows the gas to be sampled in the form of a molecular beam, thereby ensuring the efficient transmission of stable components and active components in the gas, and realizes efficient transmission of ions by combining the DC transmission electrode with the radio frequency transmission electrode, thereby realizing full-spectrum online analysis of the composition of the gas at the outlet of the aircraft engine combustion chamber.

[0048] like Figure 1 As shown, this embodiment provides an online mass spectrometry ionization source for full spectrum analysis of combustion gas components at the outlet of an aircraft engine combustion chamber, comprising an ionization source cavity and a radio frequency windowless discharge lamp 8;

[0049] The inside of the ionization source cavity is sequentially provided with a flat plate electrode 1, a cone hole electrode 2, a lamp holder electrode 3, a DC transmission electrode 4, a radio frequency transmission electrode 5 and a differential electrode 6 along the axial direction. The flat plate electrode 1, the cone hole electrode 2, the lamp holder electrode 3, the DC transmission electrode 4, the radio frequency transmission electrode 5 and the differential electrode 6 are parallel to each other, and the central through hole is coaxially arranged;

[0050] A discharge gas inlet is provided on the ionization source cavity, one end of the radio frequency windowless discharge lamp 8 is connected to the discharge gas inlet, and the other end extends into the interior of the lamp holder electrode 3;

[0051] The flat electrode 1, cone electrode 2, lamp holder electrode 3, DC transmission electrode 4, RF transmission electrode 5 and differential electrode 6 are loaded with different voltages in descending order of absolute voltage value to form an ion transmission channel in the axial direction.

[0052] The present invention changes the sampling mode of online mass spectrometry from the commonly used capillary sampling to molecular beam sampling. The molecular beam sampling form can prevent the active components in the high-temperature fuel gas from further reacting, and can only detect stable inorganic components in the fuel gas. It can also realize the detection of highly reactive species such as various free radicals and intermediates. It can be applied to the detection of fuel gas at the outlet of a real aircraft engine combustion chamber, and realizes efficient ion transmission by combining a DC transmission electrode with a radio frequency transmission electrode, which can realize full-spectrum online analysis of the fuel gas components at the outlet of the aircraft engine combustion chamber, and expand the application range of the mass spectrometer.

[0053] In this embodiment, the flat plate electrode 1, the conical hole electrode 2, and the differential electrode 6 are all plate structures with ion holes, and the shape of the ion holes is a truncated cone; the DC transmission electrode 4 and the RF transmission electrode 5 are both plate structures with a central opening; the lamp holder electrode 3 is a cylindrical structure with a central opening.

[0054] Furthermore, the flat electrode 1, conical electrode 2, and differential electrode 6 are plate-type electrodes with a conical protrusion at the center, and a through-hole for ion transmission is machined transversely at the tip of the cone. Preferably, the through-hole diameter of the flat electrode 1 is 0.3-0.5 mm, the through-hole diameter of the conical electrode 2 is 1-2 mm, and the through-hole diameter of the differential electrode 6 is 0.6-1.5 mm, with the cone angle being 40-50°.

[0055] The DC transmission electrode 4 is a circular plate structure with a through hole in the center, and the diameter of the through hole is preferably 6-8 mm;

[0056] The lamp cap electrode 3 is a cylindrical structure with a through hole in the center, and the diameter of the through hole is preferably 10-15 mm; the through hole is processed on the annular surface of the lamp cap electrode to allow the discharge lamp to extend into it, and the diameter of the through hole is preferably 6-8 mm.

[0057] The radio frequency windowless discharge lamp 8 is placed inside the ionization source cavity, perpendicular to the axis direction of the injection port, and the discharge lamp tube of the radio frequency windowless discharge lamp 8 extends into the lamp holder electrode 3.

[0058] The present invention uses a radio frequency windowless lamp as a light source. This design, without a light window, is unaffected by the harsh environment of aircraft engine combustion chambers, eliminating window contamination and enabling long-term use. Furthermore, the radio frequency windowless lamp is reduced in size and integrated within the ionization source cavity, making the ionization source more integrated while achieving a higher luminous flux.

[0059] Furthermore, the ionization source also includes a discharge gas reservoir 10 and a mass flow controller 9. The gas inlet of the RF windowless discharge lamp 8 is connected to the gas outlet of the mass flow controller 9, and the gas inlet of the mass flow controller 9 is connected to the discharge gas reservoir 10. The discharge gas reservoir 10 provides discharge gas for the RF windowless discharge lamp 8, and the flow rate of the discharge gas is controlled by the mass flow meter 9.

[0060] In this embodiment, the discharge gas stored in the discharge gas storage 10 is helium, neon, or argon, etc., and preferably has a flow rate of 10-100 mL / min.

[0061] For example, this paper uses a radio frequency windowless lamp as the light source of the online mass spectrometry ionization source, and adopts helium as the discharge gas to generate photons with energy of 21.2eV and metastable atoms / molecules of helium. Therefore, a double ionization process of VUV photoionization + Penning ionization will be generated inside the ionization source, which can achieve complete ionization of the gas components at the outlet of the aircraft engine combustion chamber.

[0062] In this embodiment, the area between the flat electrode 1 and the conical electrode 2 constitutes a gas buffer zone; the area between the conical electrode 2 and the DC transmission electrode 4 constitutes a gas component ionization zone.

[0063] The ionization source further includes a vacuum pump group, which includes an oil pump 7 and a dry pump 11. The oil pump 7 is connected to the gas buffer zone, and the dry pump 11 is connected to the gas component ionization zone.

[0064] The gas buffer area is maintained in vacuum by an oil pump 7, and the gas component ionization area is maintained in vacuum by a dry pump 11;

[0065] Preferably, the pumping speed of the oil pump is 7.6 L / s, the pumping speed of the dry pump is 3.5 L / s, the vacuum degree of the gas buffer zone is 800-2000 Pa, and the vacuum degree of the gas component ionization zone is 50-200 Pa.

[0066] In this embodiment, the RF windowless discharge lamp has a quartz discharge tube wrapped with a high-frequency coil. A high-frequency voltage is applied to the coil, causing the discharge gas in the tube to discharge and generate photons and metastable atoms / molecules. The preferred RF frequency is 133 MHz, and the peak-to-peak RF voltage is 35 V.

[0067] An ion outlet is provided on the differential electrode 6, and the ion outlet is connected to the mass spectrometer. Specifically, the ion outlet is connected to the mass spectrometer, that is, the ions obtained by ionizing the gas sample in the ionization source cavity are directly introduced into the mass spectrometer through the ion outlet on the differential electrode 6;

[0068] The RF transmission electrode 5 is a segmented quadrupole, which is composed of multiple segmented electrode rings. The electrode rings are fixed on four insulating rods placed at equal distances, and each electrode ring is isolated by insulating rings of the same size. A DC voltage is applied to the electrode ring of each pole through a voltage-dividing resistor to form a DC electric field along the axis, and at the same time, capacitors of the same capacitance are connected to apply RF voltage.

[0069] Preferably, the insulating rod is made of polyetheretherketone or ceramic.

[0070] Preferably, the dimensions of the segment quadrupole ring are: inner diameter 6 mm, outer diameter 11.5 mm, and height 8.5 mm; the dimensions of the polyetheretherketone ring are: inner diameter 6 mm, outer diameter 11.5 mm, and height 0.5 mm.

[0071] Preferably, the resistance of the voltage divider resistor is 10MΩ; the capacitance is 100nF, the frequency of the radio frequency voltage is 1.8MHz, and the peak-to-peak value is 300V.

[0072] In this embodiment, the mass spectrometer is a time-of-flight mass spectrometer, and a single detection is at the microsecond level, so that the transient change process inside the combustion chamber of the aircraft engine can be observed.

[0073] Standard gas analysis is performed on the combustion chamber outlet gas components O2, CO, CO2, H2O, NOx, and UHC of aircraft engines. Figure 2-Figure 8 The mass spectra of CO, CO2, H2O, NO, NO2, O2, and UHC obtained by the online mass spectrometry ionization source described in this embodiment. Among them, the characteristic peaks of CO and H2O are [M+H] + The characteristic peaks of the other gas products are all molecular ion peaks [M] + .

[0074] The existing composite ionization source of vacuum ultraviolet photoionization and chemical ionization relies on vacuum ultraviolet light to obtain high-concentration reagent ions. The sample and the reagent ions undergo a chemical reaction in the reaction zone and are ionized. When O2 is used as the reagent gas, only substances with a maximum ionization energy of 12.07eV can be detected. The components of the combustion gas at the outlet of an aircraft engine combustion chamber are complex, and the ionization energy of CO (14.01eV) and CO2 (13.78eV) are higher than 12.07eV. Samples with higher ionization energies such as CO (14.01eV) and CO2 (13.78eV) cannot be detected. Therefore, this ionization source cannot complete the detection of the above-mentioned high-ionization energy substances and is not suitable for the detection of the components of the combustion gas at the outlet of an aircraft engine combustion chamber of the present invention.

[0075] In the online mass spectrometry ionization source for combustion gas at the outlet of an aircraft engine combustion chamber of the present invention, the combustion gas is sampled in the form of a molecular beam, ensuring efficient transmission of stable and active components in the combustion gas. Helium is used as the discharge gas to generate photons with an energy of 21.2 eV and metastable atoms / molecules of helium, producing a dual ionization process of VUV photoionization + Penning ionization within the ionization source, thereby achieving complete ionization of the combustion gas components at the outlet of the aircraft engine combustion chamber. The source has excellent practical application value when used in conjunction with a mass spectrometer.

[0076] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A mass spectrometry ionization source for online detection of gas composition at the outlet of an aircraft engine combustion chamber, characterized in that: It comprises an ionization source cavity and a radio frequency windowless discharge lamp (8), wherein a flat plate electrode (1), a cone hole electrode (2), a lamp head electrode (3), a DC transmission electrode (4), a radio frequency transmission electrode (5) and a differential electrode (6) are sequentially arranged inside the ionization source cavity along the axial direction, and the multiple electrodes are parallel to each other and the central through hole is coaxially arranged; A discharge gas inlet is provided on the ionization source cavity, one end of the radio frequency windowless discharge lamp (8) is connected to the discharge gas inlet, and the other end extends into the interior of the lamp cap electrode (3); The flat electrode (1), the cone electrode (2), the lamp head electrode (3), the DC transmission electrode (4), the radio frequency transmission electrode (5) and the differential electrode (6) are sequentially loaded with different voltages in descending order of absolute voltage values, thereby forming an ion transmission channel in the axial direction; The flat plate electrode (1), the conical hole electrode (2) and the differential electrode (6) are all plate electrodes with a conical protrusion at the center, and the tip of the cone is processed with a through hole for ion transmission along the transverse direction; The lamp holder electrode (3) is a cylindrical structure with a through hole provided at the center; The DC transmission electrode (4) and the RF transmission electrode (5) are both plate-type structures with a central opening; The area between the flat electrode (1) and the cone electrode (2) constitutes a gas buffer zone; the area between the cone electrode (2) and the DC transmission electrode (4) constitutes a gas component ionization zone; The radio frequency transmission electrode (5) adopts a segmented quadrupole, which is composed of a plurality of segmented electrode rings. The electrode rings are fixed on four insulating rods placed at equal intervals, and each electrode ring is isolated by insulating rings of the same size. A DC voltage is applied to the electrode ring of each pole through a voltage-dividing resistor to form a DC electric field along the axis, and at the same time, capacitors of the same capacitance are connected to apply radio frequency voltage.

2. A mass spectrometry ionization source for online detection of combustion gas components at the outlet of an aircraft engine combustion chamber according to claim 1, characterized in that: The through hole diameter of the flat electrode (1) is 0.3-0.5 mm, the through hole diameter of the cone hole electrode (2) is 1-2 mm, the through hole diameter of the differential electrode (6) is 0.6-1.5 mm, and the cone hole angle is 40-50 degrees.

3. The mass spectrometry ionization source for online detection of combustion gas components at the outlet of an aircraft engine combustion chamber according to claim 1, characterized in that: The ionization source further comprises a discharge gas storage (10) and a mass flow controller (9), the air inlet end of the radio frequency windowless discharge lamp (8) is connected to the air outlet end of the mass flow controller (9), and the air inlet end of the mass flow controller (9) is connected to the discharge gas storage (10).

4. A mass spectrometry ionization source for online detection of combustion gas components at the outlet of an aircraft engine combustion chamber according to claim 3, characterized in that: The discharge gas stored in the discharge gas storage (10) is helium, neon or argon.

5. The mass spectrometry ionization source for online detection of gas composition at the outlet of an aircraft engine combustion chamber according to claim 1, characterized in that: The ionization source further comprises a vacuum pump group, which comprises an oil pump (7) and a dry pump (11), wherein the oil pump (7) is connected to the gas buffer zone, and the dry pump (11) is connected to the gas component ionization zone.

6. The mass spectrometry ionization source for online detection of combustion gas components at the outlet of an aircraft engine combustion chamber according to claim 1, characterized in that: The discharge tube in the radio frequency windowless discharge lamp (8) is made of quartz, and a high-frequency coil is wound around the discharge tube. A high-frequency voltage is applied to the high-frequency coil, and the discharge gas discharges in the discharge tube to generate photons and metastable atoms / molecules.

7. The mass spectrometry ionization source for online detection of combustion gas components at the outlet of an aircraft engine combustion chamber according to claim 1, characterized in that: An ion outlet is provided on the differential electrode (6), and the ion outlet is connected to a mass spectrometer.

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