External distributor anode integrated structure of passageway for low-power Hall thruster
Technical Field
The invention relates to a radial air outlet distributor structure, which is suitable for a Hall thruster and belongs to the technical field of Hall thruster air homogenization measures.
Background
The Hall thruster mainly comprises a hollow cathode, a discharge chamber, a magnetic pole, a magnetic coil, an anode/gas distributor, a propellant conveying pipeline and a supporting structure; the Hall propulsion technology can increase the effective load of the spacecraft, reduce the launching cost and prolong the service life, and is an effective means for improving the efficiency of commercial satellites and increasing the competitiveness in the future.
The Hall thruster comprises a hollow cathode, a discharge chamber, magnetic poles (comprising a front magnetic pole plate, a rear magnetic pole plate, an inner magnetic pole, an outer magnetic pole, an inner magnetic screen and an outer magnetic screen), an inner magnetic coil, an outer magnetic coil, an anode/gas distributor, a propellant conveying pipeline, a supporting structure and the like. The working principle is as follows: part of electrons emitted by the cathode enter the discharge chamber, drift towards the anode under the combined action of the orthogonal radial magnetic field and the axial electric field, and collide with neutral propellant atoms from the anode/gas distributor in the drift process, so that working medium atoms are ionized. Because of the existence of strong radial magnetic field, the jet-out is carried out at high speed along the axial direction under the action of the axial electric field, thereby generating thrust. Meanwhile, another part of electrons emitted by the cathode are neutralized with the axially ejected ions, and the macroscopic electric neutrality of the thruster plume is maintained. The power of the existing Hall thruster applied internationally on the track is about hundreds of watts to thousands of watts, the width of a Hall thruster channel with the power in the range is larger, therefore, a distributor is often arranged in the channel, which is a common structural form of the existing Hall thruster, the specific structural form of the distributor is shown in figure 1, and the distributor is composed of an air guide column, a fixed column, a distributor seat, a single-row pore plate, a double-row pore plate, an outer cover plate and an inner cover plate, and the materials are usually stainless steel materials. . As hall thrusters move toward lower power, the size of the channel also decreases with decreasing power. If a conventional dispenser arrangement is used. The sizes of all parts of the distributor can be very small, so that the machining and welding of the parts of the distributor have difficulty in implementation.
In the prior art, a part of the buffer chamber may be added to the structure, and the distributor is disposed in the buffer chamber, as shown in fig. 2, where the inside of the dashed frame is the buffer chamber structure. However, the increase of the buffer chamber may increase the size of the outer profile and the weight of the thruster, and in addition, the buffer chamber and the discharge channel are often designed integrally, and the material of the buffer chamber and the discharge channel may be the same, and the cost of the discharge channel is high because the ceramic composition of the discharge channel is special. Therefore, the design concept of the low-power Hall thruster pursuing light weight and low cost is contrary to the design concept of adopting a buffer cavity structure form.
Disclosure of Invention
The technical problem solved by the invention is as follows: the invention provides an external distributor structure which improves the prior art means, and the distributor structure decouples the distributor and the ceramic channel in design, the design of the distributor is not limited by the ceramic channel any more, and the distributor structure does not need to be added with a buffer cavity structure. The lightweight design of the low-power Hall thruster is facilitated.
The technical scheme of the invention is as follows: an external distributor anode integrated structure for a Hall thruster comprises an air guide column, a fixed column, an air inlet cavity, a single-row hole cavity, a double-row hole cavity and a channel cavity; the air guide column is inserted into a through hole in the air inlet chamber, and is stably connected with the air inlet chamber in an electron beam welding mode; the fixing column is inserted into a through hole in the air inlet chamber, and the fixing column is stably connected with the air inlet chamber in an electron beam welding mode; the single-row hole chamber is inserted into the air inlet chamber, and the stable connection between the air inlet chamber and the single-row hole chamber is realized by adopting an electron beam welding mode; the double-row hole chamber is inserted into the single-row hole chamber, and the single-row hole chamber and the double-row hole chamber are stably connected by adopting an electron beam welding mode; and inserting the channel chamber into the double-row hole chamber, and realizing the stable connection of the double-row hole chamber and the channel chamber by adopting an electron beam welding mode.
The gas guide column is a cylindrical structure, the cylindrical structure comprises a thread, the thread is positioned on the cylindrical surface with the largest diameter of the cylindrical structure, the thread is M4 or M5, and the thread starts from one end face of the cylindrical structure and is 10mm in length; the cylindrical structure also comprises a through hole which is coaxial with the largest cylindrical surface, and the diameter of the through hole is 2 mm.
The fixed column is of a cylindrical structure, the cylindrical structure comprises a thread, the thread is positioned on the cylindrical surface with the largest diameter of the cylindrical structure, the size of the thread is the same as that of the thread contained in the air guide column, and the length of the thread is the same as that of the thread contained in the air guide column from one end face of the cylindrical structure; the length of the air guide column is the same as that of the fixed column, and the diameter of the cylindrical surface with the maximum diameter is the same;
the air inlet chamber is of a circular ring structure and comprises a first end face and a second end face, the first end face and the second end face are arranged in parallel, the first end face extends radially inwards in the whole circumferential direction to form a first protruding portion, the first protruding portion comprises through holes, the through holes are evenly distributed in the whole circumferential direction, the number of the through holes is equal to the sum of the number of the air guide columns and the number of the fixing columns, the diameter of each through hole is the same as the diameter of the maximum-diameter cylindrical surfaces of the air guide columns and the fixing columns, the second end face extends inwards in the whole circumferential direction to form a second protruding portion, the first protruding portion and the second protruding portion have the same protruding height, and the protruding height is larger than the diameter of the maximum diameter of the air guide columns and the fixing columns. The first protruding part and the second protruding part form an annular groove with the inner side wall of the circular ring;
the single-row hole chamber is of a circular ring structure and comprises a first end face and a second end face which are arranged in parallel, the first end surface extends radially inward in the entire circumferential direction to form a first projection, the second end surface extends inward in the entire circumferential direction to form a second projection, the first and second protrusions have the same protrusion height, and form an annular groove with the inner side wall of the ring, a row of small through holes with the diameter of 0.5mm are arranged on the circular ring, the number of the small through holes is 10, the small through holes are uniformly distributed in the whole circumferential direction, the axes of the small through holes are positioned on the same plane, the plane is parallel to a first end face and a second end face of the circular ring, and the distance between the plane and the first end face is equal to that between the plane and the second end face;
the double-row hole chamber is of a circular ring structure and comprises a first end face and a second end face, the first end face and the second end face are arranged in parallel, the first end face radially and inwards extends in the whole circumferential direction to form a first protruding portion, the second end face inwards extends in the whole circumferential direction to form a second protruding portion, the first protruding portion and the second protruding portion have the same protruding height, the first protruding portion and the second protruding portion and the inner side wall of the ring form an annular groove, two rows of small through holes with the diameter of 0.5mm are arranged on the ring and are respectively a first row of small through holes and a second row of small through holes, the number of the first row of small through holes is 10, the first row of small through holes are evenly arranged in the whole circumferential direction, the axes of the first row of small through holes are located on the same plane, and the plane is parallel to the first end face and the second end face of the ring, the distance between the plane and the first end face is equal to 1/2 of the distance between the plane and the second end face, the number of the second row of small through holes is 10, the second row of small through holes are uniformly distributed in the whole circumferential direction, the axes of the second row of small through holes are located on the same plane, the plane is parallel to the first end face and the second end face of the circular ring, and the distance between the plane and the first end face is equal to 2 times of the distance between the plane and the second end face;
the channel chamber is of a circular ring structure and comprises a first cylindrical surface, a second cylindrical surface, a first end surface and a second end surface, the first cylindrical surface and the second cylindrical surface are coaxially arranged, the diameter of the first cylindrical surface is larger than that of the second cylindrical surface, the first end surface and the second end surface are arranged in parallel, the direction of the first end surface pointing to the second end surface is an extending direction, the first cylindrical surface extends in the extending direction in the whole circumferential direction to form a first protruding part, the second cylindrical surface extends in the extending direction in the whole circumferential direction to form a second protruding part, the first protruding part and the second protruding part have the same protruding height, the first protruding part and the second protruding part form an annular groove with the second end surface, the first protruding part comprises a row of small holes with the diameter of 0.5mm, and the number of the small through holes is 10, the small through holes are uniformly distributed in the whole circumferential direction, the axes of the small through holes are located on the same plane, the plane is parallel to the first end face and the second end face of the circular ring, and the distance between the plane and the first end face is 5 mm.
The air guide column, the fixing column, the air inlet chamber, the single-row hole chamber and the double-row hole chamber are made of non-magnetic stainless steel materials, and the channel chamber is made of soft magnetic alloy 1J22 materials. The number of the air guide columns is 1, the number of the fixed columns is 1 or 2 or 3, the number of the air inlet chambers is 1, the number of the single-row hole chambers is 1, the number of the double-row hole chambers is 1, and the number of the channel chambers is 1;
the air guide column is inserted into any through hole on the first protruding part of the air inlet chamber, and the air guide column is stably connected with the air inlet chamber in an electron beam welding mode; inserting the fixing column into the residual through hole of the first protruding part of the air inlet cavity, and stably connecting the fixing column with the air inlet cavity in an electron beam welding mode; inserting the single-row hole cavity into the air inlet cavity, wherein the first protruding part of the air inlet cavity is coplanar with the first protruding part of the single-row hole cavity, the second protruding part of the air inlet cavity is coplanar with the second protruding part of the single-row hole cavity, and the air inlet cavity and the single-row hole cavity are stably connected by adopting an electron beam welding mode; inserting the double-row hole cavity into the single-row hole cavity, wherein the first protruding part of the single-row hole cavity is coplanar with the first protruding part of the double-row hole cavity, the second protruding part of the single-row hole cavity is coplanar with the second protruding part of the double-row hole cavity, and the single-row hole cavity and the double-row hole cavity are stably connected by adopting an electron beam welding mode; the channel cavity is inserted into the double-row hole cavity, the first protruding portion of the double-row hole cavity is coplanar with the first end face of the channel cavity, and stable connection of the double-row hole cavity and the channel cavity is achieved in an electron beam welding mode.
Compared with the prior art, the invention has the beneficial effects that:
1. the distributor structure of the invention is different from the traditional structure in that the mixing cavity of the gas is changed from the direction along the gas inlet direction to the direction vertical to the gas inlet direction. With this arrangement, the distributor structure is no longer limited by the size of the channel. In practical application, the application on Hall thrusters with different sizes can be realized only by changing the size of the channel cavity, the expansibility is good, and the Hall thruster can be used as a universal part in the type spectrum design process of Hall thruster products. The small-size design of the low-power Hall thruster is benefited.
2. The welding mode and the materials of the invention both refer to the prior technical scheme, but the structure is simpler, and 4 parts are used to realize the mixing of gas in three layers of cavities. The channel cavity is made of magnetic materials, the magnetic screen effect is achieved, and the low-power Hall thruster is simple in structure and good in design.
3. The structure form of the invention is particularly suitable for the low-power Hall thruster, and the market prospect of the invention is better and better along with the continuous increase of the demand of the low-power Hall thruster.
Drawings
FIG. 1 shows a structure of a conventional dispenser
FIG. 2 is a schematic view of a configuration using a distributor disposed in a buffer chamber;
FIG. 3 is a block diagram of the present invention;
FIG. 4 is a three-dimensional view of the intake chamber of the present invention;
FIG. 5 is a three-dimensional view of a single row bore chamber of the present invention;
FIG. 6 is a three-dimensional view of a dual row bore chamber of the present invention;
FIG. 7 is a three-dimensional view of a channel chamber of the present invention;
FIG. 8 is a three-dimensional view of a plurality of fixed posts of the present invention;
FIG. 9 is a weld location diagram of the present invention.
Detailed Description
The invention will be further described with reference to the following description and specific examples, as illustrated in figures 2-8, in which:
an external distributor anode integrated structure for a Hall thruster is shown in figure 3 and comprises an air guide column 1, a fixing column 2, an air inlet chamber 3, a single-row hole chamber 4, a double-row hole chamber 5 and a channel chamber 6; the gas guide column 1 is inserted into a through hole in the gas inlet chamber 3, and the gas guide column 1 and the gas inlet chamber 3 are stably connected in an electron beam welding mode; the fixing column 2 is inserted into a through hole in the air inlet chamber 3, and the fixing column 2 is stably connected with the air inlet chamber 3 in an electron beam welding mode; the single-row hole chamber 4 is inserted into the air inlet chamber 3, and the air inlet chamber 3 and the single-row hole chamber 4 are stably connected in an electron beam welding mode; the double-row hole chamber 5 is inserted into the single-row hole chamber 4, and the single-row hole chamber 4 and the double-row hole chamber 5 are stably connected in an electron beam welding mode; and inserting the channel chamber 6 into the double-row hole chamber 5, and realizing the stable connection of the double-row hole chamber 5 and the channel chamber 6 by adopting an electron beam welding mode.
The gas guide column 1 is a cylindrical structure, the cylindrical structure comprises a thread, the thread is positioned on the cylindrical surface with the largest diameter of the cylindrical structure, the thread is M4 or M5, and the thread starts from one end face of the cylindrical structure and has the length of 10 mm; the cylindrical structure also comprises a through hole which is coaxial with the largest cylindrical surface, and the diameter of the through hole is 2 mm.
The fixing column 2 is a cylindrical structure, the cylindrical structure comprises a thread, the thread is positioned on the cylindrical surface with the largest diameter of the cylindrical structure, the size of the thread is the same as that of the thread contained in the gas guide column 1, and the length of the thread is the same as that of the thread contained in the gas guide column 1 from one end surface of the cylindrical structure; the length of the air guide column 1 is the same as that of the fixed column 2, and the diameter of the cylindrical surface with the maximum diameter is the same;
the air inlet chamber 3 is of an annular structure, as shown in fig. 4, and includes a first end surface and a second end surface, the first end surface and the second end surface are arranged in parallel, the first end surface extends radially inward in the whole circumferential direction to form a first protruding portion, the first protruding portion includes through holes, the through holes are uniformly arranged in the whole circumferential direction, the number of the through holes is equal to the sum of the number of the air guide columns 1 and the number of the fixed columns 2, the diameter of the through holes is the same as the diameter of the maximum diameter cylindrical surfaces of the air guide columns 1 and the fixed columns 2, the second end surface extends inward in the whole circumferential direction to form a second protruding portion, the first protruding portion and the second protruding portion have the same protruding height, and the protruding height is greater than the diameter of the maximum diameter cylindrical surfaces of the air guide columns 1 and the fixed columns 2. The first protruding part and the second protruding part form an annular groove with the inner side wall of the circular ring;
the single row of holes chamber 4 is a circular ring structure, as shown in fig. 5, and includes a first end face and a second end face, the first end surface and the second end surface are arranged in parallel, the first end surface extends radially inwards in the whole circumferential direction to form a first protruding part, the second end surface extends inwards in the whole circumferential direction to form a second protruding part, the first protruding part and the second protruding part have the same protruding height, the first and second protrusions and the inner side wall of the ring form an annular groove, a row of small through holes with the diameter of 0.5mm are arranged on the circular ring, the number of the small through holes is 10, the small through holes are uniformly distributed in the whole circumferential direction, the axes of the small through holes are positioned on the same plane, the plane is parallel to a first end face and a second end face of the circular ring, and the distance between the plane and the first end face is equal to that between the plane and the second end face;
the double-row-hole chamber 5 is of a circular ring-shaped structure and comprises a first end face and a second end face, the first end face and the second end face are arranged in parallel, the first end face extends radially inwards in the whole circumferential direction to form a first protruding portion, the second end face extends inwards in the whole circumferential direction to form a second protruding portion, the first protruding portion and the second protruding portion have the same protruding height, the first protruding portion and the second protruding portion and the inner side wall of the circular ring form an annular groove, two rows of small through holes with the diameter of 0.5mm are arranged on the circular ring and are respectively a first row of small through holes and a second row of small through holes, the number of the first row of small through holes is 10, the first row of small through holes are uniformly arranged in the whole circumferential direction, the axes of the first row of small through holes are located on the same plane, and the plane is parallel to the first end face and the second end face of the circular ring, the distance between the plane and the first end face is equal to 1/2 of the distance between the plane and the second end face, the number of the second row of small through holes is 10, the second row of small through holes are uniformly distributed in the whole circumferential direction, the axes of the second row of small through holes are located on the same plane, the plane is parallel to the first end face and the second end face of the circular ring, and the distance between the plane and the first end face is equal to 2 times of the distance between the plane and the second end face;
the channel chamber 6 is a circular ring-shaped structure, as shown in fig. 7, and includes a first cylindrical surface, a second cylindrical surface, a first end surface and a second end surface, the first cylindrical surface and the second cylindrical surface are coaxially disposed, the diameter of the first cylindrical surface is greater than that of the second cylindrical surface, the first end surface and the second end surface are disposed in parallel, the direction in which the first end surface points to the second end surface is an extending direction, the first cylindrical surface extends in the extending direction in the entire circumferential direction to form a first protruding portion, the second cylindrical surface extends in the extending direction in the entire circumferential direction to form a second protruding portion, the first protruding portion and the second protruding portion have the same protruding height, the first protruding portion and the second protruding portion form an annular groove with the second end surface, the first protruding portion includes a row of small holes with a diameter of 0.5mm, the number of the small through holes is 10, the small through holes are uniformly distributed in the whole circumferential direction, the axes of the small through holes are located on the same plane, the plane is parallel to the first end face and the second end face of the circular ring, and the distance between the plane and the first end face is 5 mm.
The air guide column 1, the fixing column 2, the air inlet chamber 3, the single-row hole chamber 4 and the double-row hole chamber 5 are made of non-magnetic stainless steel materials, and the channel chamber 6 is made of soft magnetic alloy 1J22 materials. The number of the air guide columns 1 is 1, the number of the fixed columns 2 is 1 or 2 or 3, a three-dimensional graph with the number of the fixed columns being 3 is shown in fig. 8, the number of the air inlet chambers 3 is 1, the number of the single-row hole chambers 4 is 1, the number of the double-row hole chambers 5 is 1, and the number of the channel chambers 6 is 1;
in the implementation process, an electron beam welding seam form is adopted, the welding seam is arranged as shown in fig. 9, the gas guide column 1 is inserted into any through hole on the first protruding part of the gas inlet chamber 3, and the gas guide column 1 is stably connected with the gas inlet chamber 3 in an electron beam welding mode; inserting the fixing column 2 into the residual through hole of the first protruding part of the air inlet chamber 3, and stably connecting the fixing column 2 with the air inlet chamber 3 in an electron beam welding mode; inserting the single-row hole chamber 4 into the air inlet chamber 3, wherein the first protruding part of the air inlet chamber 3 is coplanar with the first protruding part of the single-row hole chamber 4, the second protruding part of the air inlet chamber 3 is coplanar with the second protruding part of the single-row hole chamber 4, and the air inlet chamber 3 and the single-row hole chamber 4 are stably connected by adopting an electron beam welding mode; inserting the double-row hole chamber 5 into the single-row hole chamber 4, wherein the first protruding part of the single-row hole chamber 4 is coplanar with the first protruding part of the double-row hole chamber 5, the second protruding part of the single-row hole chamber 4 is coplanar with the second protruding part of the double-row hole chamber 5, and the single-row hole chamber 4 and the double-row hole chamber 5 are stably connected by adopting an electron beam welding mode; inserting the channel chamber 6 into the double-row hole chamber 5, wherein the first protruding part of the double-row hole chamber 5 is coplanar with the first end face of the channel chamber 6, and realizing the stable connection of the double-row hole chamber 5 and the channel chamber 6 by adopting an electron beam welding mode. And finally, carrying out air tightness detection on the welding seam.
The working principle of the invention is as follows:
the distributor in the Hall thruster is mainly used for realizing the homogenization of working medium gas, and because the gas is usually introduced by one gas guide column, the distributor usually adopts a multiple mixing mode to realize the homogenization of the gas. In the invention, working medium gas enters the air inlet chamber 3 from the air guide column 1, and the first mixing is realized in the annular groove of the air inlet chamber 3; then the working medium gas enters the annular groove of the single-row hole chamber 4 through the small holes on the single-row hole chamber 4 to realize the second mixing of the working medium gas; then the working medium gas enters an annular groove in the double-row hole chamber 5 through double-row small holes in the double-row hole chamber 5 to realize the third mixing of the working medium gas; then the working medium gas enters the annular groove of the channel chamber 6 through the small holes on the channel chamber 6, and then the gas impacts the second cylindrical surface on the channel chamber 6, and moves towards the discharge channel along the axial direction perpendicular to the end surface of the channel chamber 6 after being further mixed. Thereby participating in the ionization and acceleration processes in the channel. In the working process, each part is stably and reliably connected in a fusion welding mode, each welding line is subjected to gas tightness detection, and therefore gas can be prevented from leaking, and homogenization of the gas is achieved in a three-layer mixing mode.
Compared with the prior art, the size of the distributor is not limited by the size of the discharge channel like a high-power Hall thruster, and the structure of a buffer cavity does not need to be increased. Saving volume, weight and cost.
Those skilled in the art will appreciate that the details not described in the present specification are well known.