Water thruster and satellite used in space environment

Abstract

The present application discloses a water thruster and a satellite for use in a space environment. The water thruster includes a water supply unit, a vaporization unit, a discharge unit, and an injection unit. The discharge unit further heats the water vapor output from the vaporization unit through pulse discharge, so that the water thruster provides a greater injection pressure, thereby enabling the satellite to more effectively utilize the water stored in the thruster and more effectively change orbits or adjust attitudes.

Description

Technical Field

[0001] The present application relates to the field of satellite thrusters, and in particular to a water thruster and a satellite for use in a space environment. Background Art

[0002] Micro-nano satellites have the advantages of small size, low cost, short development cycle, and formation and networking. They are widely used in space science experiments and have become one of the main trends in modern satellite development. In order to achieve mission objectives such as orbit transfer, close observation, space avoidance and interception, micro-nano satellites must be equipped with a propulsion system with rapid orbital maneuverability. Currently known onboard propulsion systems include electric propulsion systems, cold gas propulsion systems, and liquid propulsion systems. They can all provide thrust for micro-nano satellites to achieve orbit transfer and attitude adjustment, but each of them has some defects. The liquid propulsion system has a complex structure, and the propellant is mostly toxic. The cost of use and maintenance is high, and there are certain limitations when applied to micro-nano satellites. The electric propulsion system and the cold gas propulsion system have small thrust, mostly at the millinewton level, and are usually used for satellite precise attitude control and slow orbital maneuvers. It is difficult to meet the mission requirements of rapid maneuvering orbit change, deorbit, space avoidance and interception.

[0003] The propulsion system using water as propellant (referred to as water propulsion system) controls the direction and attitude of the spacecraft by changing the jet pressure and jet flow rate, thus achieving precise control of the spacecraft. Compared with other space propulsion technologies, its advantages are high specific impulse, simple hardware structure, green, safe, pollution-free, and low cost.

[0004] However, the existing water propeller jet thrust is still insufficient and the water stored in the propeller cannot be used more effectively. Summary of the invention

[0005] The purpose of this application is to overcome the above-mentioned defects or problems existing in the background technology and to provide a water thruster and satellite for use in a space environment, which can provide greater jet thrust, so that the satellite can more effectively utilize the water stored in the thruster and change orbit or adjust attitude more effectively.

[0006] In order to achieve the above purpose, the following technical solutions are adopted:

[0007] A water thruster for use in a space environment, comprising: a water supply unit, which stores and supplies water; a vaporization unit, which is connected to the water supply unit and heats water and water vapor; a discharge unit, which is connected to the vaporization unit and further heats the water vapor by pulse discharge; and an injection unit, which is connected to the discharge unit and is used to inject water vapor; the water supply unit comprises a container and a water bag placed in the container, the container is filled with gas to apply pressure to the water bag, and the water bag is used to store and supply water; the vaporization unit is provided with a vaporization chamber and a first electric heater, the vaporization chamber is connected to the water bag, and the first electric heater is used to heat the water in the vaporization chamber to generate water vapor; the discharge unit is provided with a discharge cavity and a pulse voltage generator, the discharge cavity is connected to the The vaporization chamber and the injection unit, the pulse voltage generator is provided with an electrode extending into the discharge chamber and is suitable for generating a pulse voltage; the injection unit adopts a Laval nozzle, and a second electric heater is provided at the throat of the Laval nozzle; it also includes a connecting unit, the connecting unit includes a first connecting pipe, a second connecting pipe and a third connecting pipe, the first connecting pipe connects the water bag and the vaporization unit, the second connecting pipe connects the vaporization chamber and the discharge chamber, and the third connecting pipe connects the discharge chamber and the injection unit; the second connecting pipe adopts a bent pipe or a spiral pipe; it also includes a control unit, the control unit includes a controller, a first electrically controlled valve, a second electrically controlled valve, a third electrically controlled valve, a first pressure sensor, a second pressure sensor, a third pressure sensor, a fourth pressure sensor, and a fifth pressure sensor; the first electrically controlled valve, the second electrically controlled valve, and the third electrically controlled valve are respectively installed on the first connecting pipe, the second connecting pipe, and the third connecting pipe; the first pressure sensor is used to collect the gas pressure in the container; the second pressure sensor collects the water vapor pressure in the vaporization chamber, and the third pressure sensor collects the water vapor pressure in the discharge chamber; the fourth pressure sensor collects the pressure at the entrance of the Laval nozzle; the fifth pressure sensor collects the pressure at the exit of the Laval nozzle; the controller is connected to the first pressure sensor, the second pressure sensor, the third pressure sensor, the fourth pressure sensor, the fifth pressure sensor, and the The first electrically controlled valve, the second electrically controlled valve, the third electrically controlled valve, the first electric heater, the second electric heater and the pulse voltage generator are electrically connected; the controller controls the opening and closing of the first electrically controlled valve, the second electrically controlled valve, the third electrically controlled valve, the first electric heater and the pulse voltage generator according to the water vapor pressure in the vaporization chamber and the water vapor pressure in the discharge chamber; the controller also controls the opening and closing of the second electric heater according to the pressure at the inlet of the Laval nozzle and the pressure at the outlet of the Laval nozzle; the controller first performs work preparation after receiving the first injection instruction, and the work preparation includes opening the second electrically controlled valve and the third electrically controlled valve for a set time and then closing the second electrically controlled valve and the third electrically controlled valve while keeping the first electrically controlled valve closed;After the work preparation is completed, the controller performs at least one injection cycle according to the injection instruction, and each injection cycle includes the following steps: S1: open the first electrically controlled valve; S2: close the first electrically controlled valve and turn on the first electric heater when the water vapor pressure in the vaporization chamber reaches the first threshold; S3: open the second electrically controlled valve when the water vapor pressure in the vaporization chamber reaches the second threshold; S4: close the second electrically controlled valve, turn off the first electric heater and turn on the pulse voltage generator when the water vapor pressure in the discharge chamber reaches the third threshold; S5: open the third electrically controlled valve and turn off the pulse voltage generator when the water vapor pressure in the discharge chamber reaches the fourth threshold; if it is found that the pressure at the inlet of the Laval nozzle is greater than or equal to the third threshold, and the pressure at the outlet of the Laval nozzle is less than or equal to the fifth threshold, then turn on the second electric heater until the pressure at the outlet of the Laval nozzle is greater than the fifth threshold; wherein the fifth threshold is less than the first threshold, the first threshold is less than the third threshold, the third threshold is less than the second threshold, and the second threshold is less than the fourth threshold. ;

[0008] Furthermore, the first electric heater adopts a resistance heating method or a microwave heating method.

[0009] A satellite comprises a water thruster as described in any one of the above items for use in a space environment.

[0010] Compared with the prior art, the above solution has the following beneficial effects:

[0011] The present application adds a discharge unit after the vaporization unit. The discharge unit further quickly heats the water vapor through pulse discharge, so that the water vapor pressure is further increased, so that the pressure in the discharge cavity can reach twice the pressure of the vaporization chamber, thereby obtaining a higher injection pressure.

[0012] The present application pre-fills gas into the container to apply pressure to the water bag, thereby achieving effective water supply and avoiding the loss of limited energy due to water supply on the satellite.

[0013] The injection unit of the present application adopts a Laval nozzle, which can further improve the injection thrust of the water vapor.

[0014] The second connecting pipe adopts a curved pipe or a spiral pipe, which can utilize the surface tension of water in space to achieve effective water vapor separation, prevent water from entering the discharge chamber, reduce the working efficiency of the discharge chamber, and reduce invalid energy consumption.

[0015] After receiving the first injection command, the controller performs preparation work, which is conducive to exhausting the gas in the vaporization chamber. When the vaporization chamber and the discharge chamber are in a vacuum state, the water in the water bag can evaporate quickly to form water vapor, and the water vapor can also diffuse quickly from the vaporization chamber to the discharge chamber.

[0016] After the second electrically controlled valve is opened in S3, the first electric heater is not closed, which is beneficial to improving efficiency and making full use of the process of water vapor diffusing from the vaporization chamber to the discharge chamber to further increase the water vapor pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solution of the embodiment, the following briefly introduces the drawings required for use:

[0018] Figure 1 This is a schematic diagram of the structure of a water thruster used in a space environment in an embodiment;

[0019] Description of main reference numerals:

[0020] Water thruster 1; water supply unit 2; container 21; water bag 22; vaporization unit 3; vaporization chamber 31; first electric heater 32; discharge unit 4; discharge chamber 41; pulse voltage generator 42; injection unit 5; second electric heater 51; connection unit 6; first connecting pipe 61; second connecting pipe 62; third connecting pipe 63; control unit 7; controller 70; first electrically controlled valve 71; second electrically controlled valve 72; third electrically controlled valve 73; first pressure sensor 74; second pressure sensor 75; third pressure sensor 76; temperature sensor 77; fourth pressure sensor 78; fifth pressure sensor 79. DETAILED DESCRIPTION

[0021] In the claims and the description, unless otherwise defined, the terms "first", "second" or "third", etc. are intended to distinguish different objects rather than to describe a specific order.

[0022] In the claims and the specification, unless otherwise defined, terms such as "center", "lateral", "longitudinal", "horizontal", "vertical", "top", "bottom", "inside", "outside", "up", "down", "front", "back", "left", "right", "clockwise", "counterclockwise" and the like indicating directions or positional relationships are based on the directions and positional relationships shown in the drawings and are only for the convenience of simplifying the description and do not imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction.

[0023] In the claims and the specification, unless otherwise defined, the term "fixed connection" or "fixed connection" should be understood in a broad sense, that is, any connection method in which there is no displacement relationship and relative rotation relationship between the two parties, that is to say, including non-detachable fixed connection, detachable fixed connection, integral connection and fixed connection through other devices or elements.

[0024] In the claims and the description, unless otherwise defined, the terms "includes", "has" and their variations mean "including but not limited to".

[0025] The technical solutions in the embodiments will be described clearly and completely below in conjunction with the accompanying drawings.

[0026] See also Figure 1 , Figure 1 The structure of the water thruster 1 in the embodiment is shown. As shown in the figure, the water thruster 1 in the embodiment includes a water supply unit 2, a vaporization unit 3, a discharge unit 4, a spray unit 5, a connection unit 6 and a control unit 7.

[0027] The water supply unit 2 is used to store and supply water. The water supply unit 2 includes a container 21 and a water bag 22 placed in the container 21. The container 21 is filled with gas to apply pressure to the water bag 22. In this embodiment, the gas pressure reaches 20kpa. The water bag 22 is used to store and supply water.

[0028] The vaporization unit 3 is connected to the water supply unit 21 and is used to heat water and water vapor. The vaporization unit 3 is provided with a vaporization chamber 31 and a first electric heater 32. The vaporization chamber 31 is connected to the water bag 22. The first electric heater 32 is used to heat the water in the vaporization chamber 31 to generate water vapor. The first electric heater 32 can adopt a resistance heating method or a microwave heating method. The present embodiment adopts a resistance heating method. The resistor sheet is attached to the wall of the vaporization chamber.

[0029] The discharge unit 4 is connected to the vaporization unit 3 and further heats the water vapor through pulse discharge. The discharge unit 4 is provided with a discharge chamber 41 and a pulse voltage generator 42. The discharge chamber 41 is connected to the vaporization chamber 31 and the injection unit 5. The pulse voltage generator 42 is provided with an electrode extending into the discharge chamber 41 and is suitable for generating a pulse voltage. The discharge unit 4 further quickly heats the water vapor through pulse discharge, so that the water vapor pressure is further increased, so that the pressure in the discharge chamber 41 can reach twice the pressure of the vaporization chamber 31, thereby obtaining a greater injection pressure.

[0030] The spray unit 5 is connected to the discharge unit 4 and is used to spray water vapor. In this embodiment, the spray unit 5 adopts a Laval nozzle, and a second electric heater 51 is provided at the throat of the Laval nozzle. The use of the Laval nozzle can further increase the spray pressure of the water vapor. The second electric heater 51 is used to melt ice that may condense at the throat.

[0031] The connecting unit 6 includes a first connecting pipe 61, a second connecting pipe 62 and a third connecting pipe 63. The first connecting pipe 61 connects the water bag 22 and the vaporization unit 3. The first connecting pipe 6 is sealed and connected to the container 21 to ensure that the gas in the container 21 can pressurize the air bag 22. The second connecting pipe 62 connects the vaporization chamber 31 and the discharge chamber 41. In this embodiment, the second connecting pipe 62 adopts a curved pipe or a spiral pipe, which is conducive to utilizing the surface tension of water in space to achieve effective water vapor separation, prevent water from entering the discharge chamber, reduce the working efficiency of the discharge chamber, and reduce invalid energy consumption. The third connecting pipe 63 connects the discharge chamber 41 and the injection unit 5.

[0032] The control unit 7 includes a controller 70, a first electrically controlled valve 71, a second electrically controlled valve 72, a third electrically controlled valve 73, a first pressure sensor 74, a second pressure sensor 75 and a third pressure sensor 76, a temperature sensor 77, a fourth pressure sensor 78 and a fifth pressure sensor 79; the first electrically controlled valve 71, the second electrically controlled valve 72 and the third electrically controlled valve 73 are respectively installed on the first connecting pipe 61, the second connecting pipe 62 and the third connecting pipe 63. The first pressure sensor 74 is used to collect the gas pressure in the container 21; the second pressure sensor 75 collects the water vapor pressure in the vaporization chamber 31, the third pressure sensor 76 collects the water vapor pressure in the discharge chamber 41, the temperature sensor 77 collects the water vapor temperature in the vaporization chamber 31, the fourth pressure sensor 78 collects the pressure at the entrance of the Laval nozzle, and the fifth pressure sensor (79 collects the pressure at the exit of the Laval nozzle; the controller 70 is connected with the first pressure sensor 74, the second pressure sensor 75, the third pressure sensor 76, the temperature sensor 77, the fourth pressure sensor 78, the fifth pressure sensor 79, the first electric control valve 71, and the second electric control valve 72 , the third electric control valve 73, the first electric heater 32, the second electric heater 51 and the pulse voltage generator 42 are electrically connected; the controller 70 controls the first electric control valve 71, the second electric control valve 72, the third electric control valve 73, the first electric heater 32 and the pulse voltage generator 42 to open and close according to the water vapor pressure in the vaporization chamber 31 and the water vapor pressure in the discharge chamber 41, and the controller also controls the second electric heater 51 to open and close according to the pressure at the inlet of the Laval nozzle and the pressure at the outlet of the Laval nozzle. At the same time, in this embodiment, the controller 70 also monitors the gas pressure in the container 21, and also controls the working power of the first electric heater 32 according to the water vapor temperature in the vaporization chamber 31.

[0033] In this embodiment, the controller 70 performs a preparation work after receiving the first injection instruction. The preparation work includes opening the second and third electric control valves 72 and 73 for a set time and then closing the second and third electric control valves 72 and 73 while keeping the first electric control valve 71 closed. After the preparation work is completed, the controller 70 performs at least one injection cycle according to the injection instruction. Each injection cycle includes the following steps:

[0034] S1: Open the first electrically controlled valve 71;

[0035] S2: when the water vapor pressure in the vaporization chamber 31 reaches a first threshold, the first electrically controlled valve 71 is closed and the first electric heater 32 is turned on;

[0036] S3: when the water vapor pressure in the vaporization chamber 31 reaches a second threshold, the second electrically controlled valve 72 is opened;

[0037] S4: when the water vapor pressure in the discharge chamber 41 reaches a third threshold, the second electrically controlled valve 72 is closed, the first electric heater 32 is closed, and the pulse voltage generator 42 is turned on;

[0038] S5: When the water vapor pressure in the discharge chamber (41) reaches the fourth threshold value, the third electrically controlled valve 73 is opened and the pulse voltage generator 42 is closed; if it is found that the pressure at the inlet of the Laval nozzle is greater than or equal to the third threshold value, and the pressure at the outlet of the Laval nozzle is less than or equal to the fifth threshold value, the second electric heater 51 is turned on until the pressure at the outlet of the Laval nozzle is greater than the fifth threshold value.

[0039] Among them, the fifth threshold is less than the first threshold, the first threshold is less than the third threshold, the third threshold is less than the second threshold, and the second threshold is less than the fourth threshold. In this embodiment, the fifth threshold is close to 0; the first threshold is 1.5kPa, the second threshold is 4kPa, the third threshold is 3.5kPa, and the fourth threshold is 8kPa. From the above thresholds, it can be seen that the water vapor in the vaporization chamber 31 can be pressurized to 4kPa, and after the discharge unit 4 discharges, the water vapor in the discharge cavity 42 can be pressurized to 8kPa, which significantly increases the water vapor pressure, and increases the injection speed and thrust.

[0040] In the above control process, the controller 70 performs the preparation work after receiving the first injection instruction, which is conducive to exhausting the gas in the vaporization chamber 31, so that the vaporization chamber 31 and the discharge chamber 41 are both in a vacuum state, so that the water in the water bag 21 can quickly evaporate to form water vapor, and the water vapor can also quickly diffuse from the vaporization chamber 31 to the discharge chamber 41. In the above steps, after the second electric control valve 72 is opened in S3, the first electric heater 32 is still not closed, which is conducive to improving efficiency and making full use of the process of water vapor diffusing from the vaporization chamber 31 to the discharge chamber 41 to further increase the water vapor pressure.

[0041] The satellite in this embodiment uses the above-mentioned water thruster 1 used in the space environment, so the satellite can change orbit or speed more efficiently and can make fuller use of its stored water.

[0042] The above specification and description of the embodiments are used to explain the protection scope of the present application, but do not constitute a limitation on the protection scope of the present application.

Claims

1. A water thruster (1) for use in a space environment, characterized in that: include: a water supply unit (2) which stores and supplies water; A vaporization unit (3) connected to the water supply unit (21) for heating water and water vapor; A discharge unit (4), which is connected to the vaporization unit (3) and further heats the water vapor through pulse discharge; and an injection unit (5), which is connected to the discharge unit (4) and is used for injecting water vapor; The water supply unit (2) comprises a container (21) and a water bag (22) placed in the container (21); the container (21) is filled with gas to apply pressure to the water bag (22); the water bag (22) is used to store and supply water; The vaporization unit (3) is provided with a vaporization chamber (31) and a first electric heater (32), the vaporization chamber (31) is connected to the water bag (22), and the first electric heater (32) is used to heat the water in the vaporization chamber (31) to generate water vapor; the discharge unit (4) is provided with a discharge cavity (41) and a pulse voltage generator (42), the discharge cavity (41) is connected to the vaporization chamber (31) and the injection unit (5), and the pulse voltage generator (42) is provided with an electrode extending into the discharge cavity (41) and is suitable for generating a pulse voltage; The injection unit (5) adopts a Laval nozzle, and a second electric heater (51) is provided at the throat of the Laval nozzle; it also includes a connecting unit (6), the connecting unit (6) includes a first connecting pipe (61), a second connecting pipe (62) and a third connecting pipe (63), the first connecting pipe (61) connects the water bag (22) and the vaporization unit (3), the second connecting pipe (62) connects the vaporization chamber (31) and the discharge chamber (41), and the third connecting pipe (63) connects the discharge chamber (41) and the injection unit (5); the second connecting pipe (62) adopts a bent pipe or a spiral pipe; It also includes a control unit (7), the control unit (7) including a controller (70), a first electrically controlled valve (71), a second electrically controlled valve (72), a third electrically controlled valve (73), a first pressure sensor (74), a second pressure sensor (75), a third pressure sensor (76), a fourth pressure sensor (78), and a fifth pressure sensor (79); The first electrically controlled valve (71), the second electrically controlled valve (72) and the third electrically controlled valve (73) are respectively installed on the first connecting pipe (61), the second connecting pipe (62) and the third connecting pipe (63); The first pressure sensor (74) is used to collect the gas pressure in the container (21); the second pressure sensor (75) collects the water vapor pressure in the vaporization chamber (31); the third pressure sensor (76) collects the water vapor pressure in the discharge chamber (41); the fourth pressure sensor (78) collects the pressure at the inlet of the Laval nozzle; and the fifth pressure sensor (79) collects the pressure at the outlet of the Laval nozzle; The controller (70) is electrically connected to the first pressure sensor (74), the second pressure sensor (75), the third pressure sensor (76), the fourth pressure sensor (78), the fifth pressure sensor (79), the first electric-controlled valve (71), the second electric-controlled valve (72), the third electric-controlled valve (73), the first electric heater (32), the second electric heater (51) and the pulse voltage generator (42); the controller (70) controls the first electric-controlled valve (71), the second electric-controlled valve (72), the third electric-controlled valve (73), the first electric heater (32) and the pulse voltage generator (42) to open and close according to the water vapor pressure in the vaporization chamber (31) and the water vapor pressure in the discharge chamber (41); the controller (70) also controls the second electric heater (51) to open and close according to the pressure at the inlet of the Laval nozzle and the pressure at the outlet of the Laval nozzle; The controller (70) first performs a preparation operation after receiving a first injection instruction, wherein the preparation operation includes opening the second electric control valve (72) and the third electric control valve (73) for a set time and then closing the second electric control valve (72) and the third electric control valve (73) while keeping the first electric control valve (71) closed; After the preparation work is completed, the controller (70) performs at least one injection cycle according to the injection instruction, and each injection cycle includes the following steps: S1: Open the first electrically controlled valve (71); S2: when the water vapor pressure in the vaporization chamber (31) reaches a first threshold value, closing the first electrically controlled valve (71) and turning on the first electric heater (32); S3: opening the second electrically controlled valve (72) when the water vapor pressure in the vaporization chamber (31) reaches a second threshold value; S4: when the water vapor pressure in the discharge chamber (41) reaches a third threshold value, the second electrically controlled valve (72) is closed, the first electric heater (32) is closed, and the pulse voltage generator (42) is opened; S5: when the water vapor pressure in the discharge chamber (41) reaches a fourth threshold, the third electrically controlled valve (73) is opened and the pulse voltage generator (42) is closed; if it is found that the pressure at the inlet of the Laval nozzle is greater than or equal to the third threshold, and the pressure at the outlet of the Laval nozzle is less than or equal to the fifth threshold, the second electric heater (51) is turned on until the pressure at the outlet of the Laval nozzle is greater than the fifth threshold; Among them, the fifth threshold is smaller than the first threshold, the first threshold is smaller than the third threshold, the third threshold is smaller than the second threshold, and the second threshold is smaller than the fourth threshold.

2. A water thruster (1) for use in a space environment as claimed in claim 1, characterized in that: The first electric heater (32) adopts a resistance heating method or a microwave heating method.

3. A satellite, characterized in that: It comprises a water thruster (1) for use in a space environment as described in claim 1 or 2.

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