A polyatomic molecule directional flow generating device

Abstract

This application relates to the field of aerospace metrology technology, specifically to a polyatomic directional flow generation device. The device includes a directional flow generation chamber. Inside the chamber, an axially arranged radio frequency ion source, an ion acceleration module, an ion screening module, an ion neutralization module, and an ion absorption module are sequentially arranged. An radio frequency generation and pulse modulation module is mounted on the outer wall of the chamber, comprising a radio frequency signal generator, a pulse modulation module, a power amplifier, and a radio frequency coil. This application targets polyatomic molecules with complex compositions after ionization. Through active control and screening, it can generate a high-speed directional molecular flow with independently adjustable velocity and density, high gas purity, and good velocity consistency, providing a standard experimental environment simulating the orbital gas environment for space metrology instruments.

Description

Technical Field

[0001] This application relates to the field of aerospace measurement technology, and more specifically, to a device for generating directional flow of polyatomic molecules. Background Technology

[0002] Spacecraft travel at very high speeds in orbit. For example, a spacecraft orbiting the Earth typically reaches the first cosmic velocity of 7.8 knm / s. This speed is much greater than the thermal motion speed of the gas in the orbital environment. In other words, the spacecraft is in an environment of high-speed directional molecular flow. The directional molecular flow environment is very different from the static molecular environment. Under this environment, the question of whether various types of measuring instruments can accurately measure or even quantify characteristic parameters requires a lot of theoretical and experimental research. Therefore, it is necessary to establish an experimental device on the ground to simulate the high-speed directional molecular flow environment in orbit.

[0003] To simulate the actual environment under various celestial bodies and orbits, the molecular types should generally include oxygen, nitrogen, argon, hydrogen, carbon dioxide, etc. The molecular flow generation device is required to have continuous adjustment function for molecular flow density, velocity and molecular beam diameter within a certain range, good velocity consistency and high purity of gas composition.

[0004] Currently, there are two main methods for generating high-speed molecular flow. One method is to heat the gas using a Laval nozzle to achieve a higher velocity. However, this method has certain limitations, namely, the nozzle has an upper limit on the temperature it can withstand. For example, the highest operating temperature of tungsten, which is the most heat-resistant material, is around 2000℃. At this temperature, the velocity that gas molecules can reach is limited. Even hydrogen, the lightest molecular weight, can only reach a velocity of about 4 km / s. This method obviously cannot meet the requirements of larger gas molecules and higher velocities. Another approach is the neutral beam injection method used in tokamak devices. This method primarily uses hydrogen as the working medium. Neutral gas is ionized and accelerated before entering a neutralization chamber for neutralization. This method can obtain neutral gas with extremely high velocities, but it is currently only suitable for the specific operating conditions of tokamak devices. Its main characteristics are the use of hydrogen as the working medium and its extremely high velocity. However, for the aforementioned spacecraft orbital environment simulation applications, the molecules involved are mainly complex molecules such as diatomic molecules, and the molecular velocity is much lower than that of the neutral beam injection device. These molecules, after ionization and acceleration by the ion source, produce a variety of ions, including monatomic ions and diatomic ions. Furthermore, the proportion and density of different particles are uncontrollable, and ions with different charge-to-mass ratios exhibit significant velocities after acceleration. The neutral beam particles extracted after collisions in the neutralization chamber have complex compositions and poor velocity consistency. Therefore, the traditional neutral beam injection method is not suitable for the needs of orbital environment gas simulation. Summary of the Invention

[0005] This application provides a polyatomic molecular directional flow generation device, which generates a high-speed directional molecular flow with independently adjustable velocity and density, high particle purity, and good velocity consistency through active screening and control of ions.

[0006] To achieve the above objectives, this application provides a polyatomic molecule directional flow generation device, including a directional flow generation chamber. Inside the directional flow generation chamber, an axially arranged radio frequency ion source, an ion acceleration module, an ion screening module, an ion neutralization module, and an ion absorption module are sequentially arranged. Specifically: the radio frequency ion source adopts an electrodeless structure within the discharge chamber; the ion acceleration module includes an ion extraction electrode and an ion acceleration electrode; the ion screening module consists of a magnet and an electrode plate; the ion neutralization module includes a neutralization chamber, an electron source, a second gas inlet device, and a cooling device; the ion absorption module consists of an ion collecting plate; a radio frequency generation and pulse modulation module is disposed on the outer wall of the directional flow generation chamber. This module includes a radio frequency signal generator, a pulse modulation module, a power amplifier, and a radio frequency coil. The radio frequency coil is wound around the outer wall of the directional flow generation chamber and is correspondingly positioned in the region where the radio frequency ion source is located; the radio frequency signal generator is connected to the pulse modulation module; the pulse modulation module is connected to the power amplifier; and the power amplifier is connected to the radio frequency coil through a matching network.

[0007] Furthermore, a first air intake device is provided on one side of the directional flow generation chamber near the radio frequency ion source.

[0008] Furthermore, the ion extraction electrode has a positive potential relative to ground and is connected to the extraction power supply outside the directional flow generation chamber; the ion acceleration electrode has a negative potential relative to ground and is connected to the acceleration power supply outside the directional flow generation chamber.

[0009] Furthermore, there are two magnets, which are respectively set on the inner wall of the directional flow generating chamber, and the two magnets are symmetrical along the axis; there are two electrode plates, which are symmetrically set along the axis, and the electrode plates and magnets together generate an orthogonal electromagnetic field.

[0010] Furthermore, electron sources are respectively installed on the inner walls of both sides of the directional flow generation chamber and emit electrons into the neutralization chamber; a second air intake device is installed on the other side of the directional flow generation chamber and supplies air into the neutralization chamber; cooling devices are respectively installed on the outer walls of both sides of the directional flow generation chamber and are used to cool the gas in the neutralization chamber.

[0011] Furthermore, the ion neutralization module includes two neutralization methods: charge exchange collisions between the target ion and background gas molecules, and the target ion capturing electrons emitted by the electron source.

[0012] Furthermore, there are two ion collecting plates, which are respectively set on the inner walls on both sides of the directional flow generation chamber and are symmetrical along the axial direction; the ion collecting plates have a negative potential relative to ground.

[0013] Furthermore, it also includes a neutral beam diameter control module, which consists of a beam diameter adjuster, the center aperture of which can be adjusted.

[0014] Furthermore, the radio frequency signal generator can generate continuous radio frequency signals.

[0015] Furthermore, the pulse modulation module is capable of applying pulse modulation with adjustable duty cycle and frequency.

[0016] The polyatomic molecule directional flow generating device provided in this application has the following beneficial effects:

[0017] This application targets polyatomic molecules with complex compositions after ionization. Through active regulation and screening, it can form a high-speed directional molecular flow with independently adjustable velocity and density, high gas purity, and good velocity consistency. This can provide a standard test environment that simulates the orbital gas environment for space metrology-related instruments. Attached Figure Description

[0018] The accompanying drawings, which form part of this application, are used to provide a further understanding of the application and to make other features, objects, and advantages of the application more apparent. The illustrative embodiments and descriptions of this application are used to explain the application and do not constitute an undue limitation of the application. In the drawings:

[0019] Figure 1 This is a schematic diagram of a polyatomic molecule directional flow generating device provided according to an embodiment of this application;

[0020] In the figure: 1-Directional flow generation chamber, 2-First air intake device, 3-RF coil, 4-Ion extraction electrode, 5-Ion acceleration electrode, 6-Magnet, 7-Electrode plate, 8-Neutralization chamber, 9-Electron source, 10-Second air intake device, 11-Cooling device, 12-Ion collection plate, 13-Beam diameter adjuster, 14-RF signal generator, 15-Pulse modulation module, 16-Power amplifier, 17-Matching network, 18-Extraction power supply, 19-Accelerating power supply, 20-RF ion source. Detailed Implementation

[0021] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0022] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0023] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0024] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0025] In addition, the term "multiple" should mean two or more.

[0026] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0027] like Figure 1As shown, this application provides a polyatomic molecule directional flow generation device, including a directional flow generation chamber 1. Inside the directional flow generation chamber 1, an axially arranged radio frequency ion source 20, an ion acceleration module, an ion screening module, an ion neutralization module, and an ion absorption module are sequentially arranged. Specifically: the radio frequency ion source 20 adopts an electrodeless structure within the discharge chamber; the ion acceleration module includes an ion extraction electrode 4 and an ion acceleration electrode 5; the ion screening module consists of a magnet 6 and an electrode plate 7; and the ion neutralization module includes a neutralization chamber 8, an electron source 9, and a second air intake device 1. 0 and cooling device 11; ion absorption module consists of ion collection plate 12; radio frequency generation and pulse modulation module is provided on the outer wall of directional flow generation chamber 1; the radio frequency generation and pulse modulation module includes radio frequency signal generator 14, pulse modulation module 15, power amplifier 16 and radio frequency coil 3, wherein: radio frequency coil 3 is wound on the outer wall of directional flow generation chamber 1 and is correspondingly set in the area where radio frequency ion source 20 is located; radio frequency signal generator 14 is connected to pulse modulation module 15; pulse modulation module 15 is connected to power amplifier 16; power amplifier 16 is connected to radio frequency coil 3 through matching network 17.

[0028] Specifically, the polyatomic molecule directional flow generation device provided in this application, targeting polyatomic molecules with complex compositions after ionization, can form a high-speed directional molecular flow with independently adjustable velocity and density, high gas purity, and good velocity consistency through active regulation and screening. The device consists of a directional flow generation chamber 1, inside which, from left to right, are arranged a radio frequency ion source 20, an ion acceleration module, an ion screening module, an ion neutralization module, and an ion absorption module. Externally, a radio frequency generation and pulse modulation module is arranged for pulse modulation of the radio frequency ion source 20. In this process, the radio frequency ion source 20, under the action of the pulse modulation module 15, the power amplifier 16, and the radio frequency coil 3, ionizes the gas molecules inside the directional flow generation chamber 1 into various ions. After being accelerated to a certain speed by the ion acceleration module, the various ions enter the ion screening module. The ion screening module ensures that only target ions can pass along the axial direction through the orthogonal electromagnetic field formed by the magnet 6 and the electrode plate 7. After the target ions enter the ion neutralization module, they collide with the neutral molecules and electrons inside the neutralization chamber 8 to achieve ion neutralization. After the beam dominated by neutral molecules enters the ion absorption module, it will generate a high-speed and high-purity directional molecular flow, while the unneutralized ions will deviate from the axial direction under the action of the electric field.

[0029] Furthermore, a first gas inlet device 2 is provided on one side of the directional flow generation chamber 1 near the radio frequency ion source 20. The first gas inlet device 2 is located in the area where the radio frequency ion source 20 is located, and is used to introduce working gas into the directional flow generation chamber 1, so that the working gas undergoes continuous collision ionization under the action of the radio frequency electromagnetic field, thereby generating various types of ions.

[0030] Furthermore, the ion extraction electrode 4 has a positive potential relative to ground and is connected to the extraction power supply 18 outside the directional flow generation chamber 1; the ion acceleration electrode 5 has a negative potential relative to ground and is connected to the acceleration power supply 19 outside the directional flow generation chamber 1. The ion acceleration module includes the ion extraction electrode 4 with a positive potential relative to ground and the ion acceleration electrode 5 with a negative potential relative to ground. By applying a certain voltage combination to the two electrodes through the extraction power supply 18 and the acceleration power supply 19, all ions in the directional flow generation chamber 1 can be extracted at a certain speed. The extraction speed is determined by both the net acceleration voltage and the ion mass.

[0031] Furthermore, there are two magnets 6, each set on the inner wall of the directional flow generation chamber 1, symmetrically arranged along the axial direction; there are also two electrode plates 7, symmetrically arranged along the axial direction; the electrode plates 7 and the magnets 6 together generate orthogonal electromagnetic fields. The ion screening module consists of two sets of magnets 6 and electrode plates 7 arranged in parallel and symmetrical order. The magnets 6 can be electromagnets or permanent magnets. The magnets 6 and the electrode plates 7 together generate orthogonal electromagnetic fields. According to the charge, mass, and velocity of the target ions, appropriate electric and magnetic field strengths are selected so that the electric force and Lorentz force on the target ions cancel each other out, thus allowing only the target ions to pass along the axial direction, while other ions deviate from the axial direction.

[0032] Furthermore, electron sources 9 are respectively disposed on the inner walls of both sides of the directional flow generating chamber 1 and emit electrons into the neutralization chamber 8; the second air intake device 10 is disposed on the other side of the directional flow generating chamber 1 and supplies air into the neutralization chamber 8; the cooling device 11 is respectively disposed on the outer walls of both sides of the directional flow generating chamber 1 and is used to cool the gas in the neutralization chamber 8.

[0033] Furthermore, the ion neutralization module includes two neutralization methods: charge exchange collisions between the target ion and background gas molecules, and the target ion capturing electrons emitted by the electron source 9.

[0034] Specifically, the electron source 9 is mainly used to emit electrons into the neutralization chamber 8, the second gas inlet device 10 is mainly used to provide background gas into the neutralization chamber 8, and the cooling device 11 is mainly used to cool the gas inside the neutralization chamber 8. In this embodiment, the ion neutralization module operates in two ways: the first is that the high-speed target ions collide with the thermally moving background gas molecules through charge exchange, producing high-speed neutral molecules and low-speed ions. Since the higher the thermal velocity of the background gas molecules, the easier it is for the high-speed molecules to deviate from their direction of motion after the charge exchange collision. To reduce this effect, a cooling device 11 is added outside the neutralization chamber 8 to reduce the thermal velocity of the background gas molecules. The second is that the high-speed target ions capture the electrons emitted by the electron source 9, thereby producing high-speed neutral molecules. The combined effect of the two neutralization methods can effectively improve the neutralization efficiency without changing the transport path of the high-speed molecular beam.

[0035] Furthermore, there are two ion collecting plates 12, which are respectively arranged on the inner walls of both sides of the directional flow generation chamber 1, symmetrically along the axial direction; the ion collecting plates 12 have a negative potential relative to ground. The ion absorption module consists of two symmetrically arranged ion collecting plates 12 with a negative potential relative to ground, which can cause unneutralized ions drawn out from the neutralization chamber 8 to deviate from the axial direction and escape from the neutral beam.

[0036] Furthermore, it also includes a neutral beam diameter adjustment module, which consists of a beam diameter adjuster 13, the center aperture of which is adjustable. The neutral beam diameter adjustment module, consisting of a beam diameter adjuster 13 with an adjustable center aperture, can flexibly adjust the diameter of the passing neutral beam according to actual needs.

[0037] Furthermore, the radio frequency signal generator 14 is capable of generating continuous radio frequency signals.

[0038] Furthermore, the pulse modulation module 15 is capable of applying pulse modulation with adjustable duty cycle and frequency.

[0039] Specifically, in this embodiment, the radio frequency ion source 20 adopts an electrodeless structure within the discharge chamber, which can adapt to various reactive gases and polyatomic molecular gases. By applying radio frequency excitation to the radio frequency coil 3 wound around the outer wall of the directional flow generation chamber 1, an induced electromagnetic field is generated within the directional flow generation chamber 1. The working gas is introduced through the first gas inlet device 2, and the gas undergoes continuous collisional ionization under the action of the radio frequency electromagnetic field, thereby generating various types of ions. Among them, the radio frequency signal generator 14 is mainly used to generate a continuous radio frequency signal. Based on this, the pulse modulation module 15 performs periodic pulse modulation with adjustable duty cycle and frequency. The modulated signal is transmitted to the radio frequency coil 3 through the power amplifier 16 and the matching network 17. The pulse signal is used as a switch to periodically regulate the ignition and annihilation process of the radio frequency discharge, turning the continuous radio frequency discharge into an intermittent discharge. Compared with conventional radio frequency discharge, pulse-modulated radio frequency discharge introduces two parameters, pulse frequency and duty cycle, which can flexibly regulate the discharge plasma parameters, such as electron density, electron temperature, particle composition and particle ratio, thereby effectively regulating the ratio of different ions in the directional flow generation chamber 1, so that the proportion of target ions reaches the highest level, thus realizing the density regulation of molecular directional flow at the ion generation stage.

[0040] More specifically, the process of directional flow generation is as follows: The working gas enters the discharge chamber of the radio frequency ion source 20 through the first inlet device 2 at a certain flow rate. Under the action of the radio frequency induced electromagnetic field, it is ionized to form plasma. Since the particle composition after ionization of polyatomic molecules is complex, by applying pulse modulation with a certain duty cycle and frequency to the radio frequency excitation signal, it is possible to actively control ions with various charge-to-mass ratios in the directional flow generation chamber 1, thereby enabling specific target ions to reach the required density. Ions with different charge-to-mass ratios are extracted through the ion acceleration module. By applying a certain voltage between the two electrodes of the acceleration module, all ions are accelerated. Different voltages can be applied according to the speed requirements. The accelerated ions enter the ion screening module. The ion screening module forms an orthogonal electromagnetic field with magnet 6 and parallel electrode plates 7. According to the target... By selecting the target ion's charge-to-mass ratio and velocity parameters, and choosing appropriate electric and magnetic field strengths, only the target ions are allowed to pass through the screening module along the axial direction; other types of ions will deviate from the axial direction. The high-speed target ions that pass through the screening enter the ion neutralization module. In the ion neutralization module, two neutralization methods work together to improve neutralization efficiency. One method is that the target ions and the corresponding neutral molecules exchange charges and collide to achieve neutralization. The other method is that the electron source 9 continuously emits electrons, and the ions capture electrons to achieve neutralization. After the two methods work together, a high-speed molecular stream dominated by target molecules is formed. The unneutralized ions are absorbed by the ion collection plate 12 with a negative potential relative to ground. Finally, the neutral beam is controlled by the neutral beam diameter control module, thereby realizing the generation of a high-purity, high-speed directional stream of polyatomic molecules with adjustable velocity density.

[0041] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A multi-atomic molecule directed flow generating device comprising a directed flow generating chamber, characterized by, The directional flow generation chamber contains, along its axial direction, a radio frequency ion source, an ion acceleration module, an ion screening module, an ion neutralization module, and an ion absorption module arranged sequentially, wherein: The radio frequency ion source adopts an electrodeless structure in the discharge chamber for ionizing polyatomic molecular gases; The ion acceleration module includes an ion extraction electrode and an ion acceleration electrode; The ion screening module consists of magnets and electrode plates, and is used to select ions with a specific charge-to-mass ratio in an orthogonal electromagnetic field; There are two magnets, which are respectively disposed on the inner wall of the directional flow generating chamber, and the two magnets are symmetrical along the axial direction; there are two electrode plates, which are symmetrically disposed along the axial direction, and the electrode plates and the magnets together generate orthogonal electromagnetic fields. The ion neutralization module includes a neutralization chamber, an electron source, a second air intake device, and a cooling device. The cooling device is used to reduce the thermal velocity of the background gas in the neutralization chamber; The ion absorption module consists of an ion collecting plate; A radio frequency (RF) generation and pulse modulation module is disposed on the outer wall of the directional flow generation chamber. The RF generation and pulse modulation module includes an RF signal generator, a pulse modulation module, a power amplifier, and an RF coil, wherein: The radio frequency coil is wound around the outer wall of the directional flow generation chamber and is correspondingly positioned in the region where the radio frequency ion source is located. The radio frequency signal generator is connected to the pulse modulation module; The pulse modulation module is capable of applying pulse modulation with adjustable duty cycle and frequency; The pulse modulation module is connected to the power amplifier; The power amplifier is connected to the radio frequency coil via a matching network; It also includes a neutral beam diameter control module, which consists of a beam diameter adjuster, the center aperture of which is adjustable.

2. The polyatomic molecule directional flow generating device according to claim 1, characterized in that, A first air intake device is provided on one side of the directional flow generation chamber near the radio frequency ion source.

3. The polyatomic molecule directional flow generating device according to claim 1, characterized in that, The ion extraction electrode has a positive potential relative to ground and is connected to the extraction power supply outside the directional flow generating chamber; the ion acceleration electrode has a negative potential relative to ground and is connected to the acceleration power supply outside the directional flow generating chamber.

4. The polyatomic molecule directional flow generating device according to claim 1, characterized in that, The electron source is disposed on the inner wall of both sides of the directional flow generating chamber and emits electrons into the neutralization chamber; the second air intake device is disposed on the other side of the directional flow generating chamber and supplies air into the neutralization chamber; the cooling device is disposed on the outer wall of both sides of the directional flow generating chamber and is used to cool the gas in the neutralization chamber.

5. The polyatomic molecule directional flow generating device according to claim 4, characterized in that, The ion neutralization module includes two neutralization methods: target ions undergoing charge exchange collisions with background gas molecules, and target ions capturing electrons emitted by the electron source.

6. The polyatomic molecule directional flow generating device according to claim 1, characterized in that, There are two ion collecting plates, which are respectively disposed on the inner walls on both sides of the directional flow generating chamber and are symmetrical along the axial direction; the ion collecting plates have a negative potential relative to ground.

7. The polyatomic molecule directional flow generating device according to claim 1, characterized in that, The radio frequency signal generator is capable of generating continuous radio frequency signals.

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