A splash protection system and method for electric propulsion ignition testing

Abstract

This invention relates to the field of aerospace technology and discloses an anti-splash system and method for electric propulsion ignition testing. It addresses the problems of existing vacuum chamber anti-splash systems being difficult to disassemble and transport, and requiring active cooling during thrust beam bombardment, which increases the cost of thruster ignition testing. The anti-splash system includes two headed anti-splash targets 1 and a chamber anti-splash target 2, both housed within the vacuum chamber. The two headed anti-splash targets 1 are positioned on either side of the chamber anti-splash target 2 without spacing. The bottom of the chamber anti-splash target 2 is flat and is mounted on a guide rail on the top of a docking trolley 3. The electric thruster anti-splash system designed in this invention adopts a modular design, with each module docking with the vacuum chamber via pulleys. This facilitates disassembly, transportation, and maintenance of the proposed device, reducing equipment maintenance and transportation costs.

Description

Technical Field

[0001] This invention relates to a splash protection system and method for electric propulsion ignition testing, belonging to the field of aerospace technology. Background Technology

[0002] The detector is equipped with an electric propulsion subsystem, and a whole-device-level electric propulsion ignition test needs to be carried out on the structural thermal controller. The whole device needs to verify the ability of the electric propulsion system to operate normally under the support of the primary power supply subsystem and the GNC subsystem in a vacuum environment, as well as the impact of the electric propulsion subsystem on other related subsystem products of the whole device during operation.

[0003] In the vacuum state electric propulsion ignition test of the entire detector, the high-energy plume particles generated by electric propulsion cause contamination to the detector and vacuum chamber by their sputtering products. Most existing vacuum chamber sputter protection systems adopt an integrated structure, which is inconvenient to disassemble and transport. At the same time, the sputter protection target in the integrated structure also needs to be actively cooled to withstand the continuous bombardment of the thruster beam, which increases the cost of thruster ignition test. The invention patent with publication number CN115556972B discloses an electric propulsion test plume sputter protection system, which includes at least a front beam shield, a peripheral sputter protection screen, and a dark area beam shield. The cavity enclosed by the three is approximately closed and forms a sandwich with the vacuum container, and the electric thruster is located in the cavity. The front beam shield is arranged in front of the electric thruster, the dark area beam shield is arranged in rear of the electric thruster, and the peripheral sputter protection screen is cylindrical and located between the front beam shield and the dark area beam shield. The invention patent with publication number CN107340139A discloses a sputtering target device for ignition testing of an electric propulsion spacecraft system. The top of the shield has an opening for receiving plume particles, and the main target is set on the bottom of the shield opposite the opening. The main target is made of a low sputtering rate material. The shield has a multi-layer flow guiding structure. When sputtered particles pass through it, they collide multiple times, increasing their adsorption probability on the wall surface. Unadsorbed particles are guided by the flow guiding structure to non-sensitive surfaces inside the container. The problem with the above two patents is that they need to rely on active cooling devices to deal with the thrust beam bombardment, and the time they can withstand the thrust beam bombardment is relatively short. Summary of the Invention

[0004] To address the problems of existing vacuum chamber splashback protection systems being inconvenient to disassemble and transport, and requiring active cooling during thruster beam bombardment, which increases the cost of thruster ignition tests, this invention proposes a splashback protection system and method for electric propulsion ignition tests.

[0005] The technical solution adopted by the present invention to solve the above problems is: an anti-splashing system for electric propulsion ignition testing proposed in the present invention, comprising:

[0006] Two headed anti-splash targets (1) and a body anti-splash target (2) are installed inside the vacuum chamber. The two headed anti-splash targets (1) are installed on both sides of the body anti-splash target (2) without any gap.

[0007] Furthermore, the anti-splash system for electric propulsion ignition test also includes two sets of parallel support rails for the head anti-splash target (1) and the body anti-splash target (2) located in the vacuum chamber. The two sets of rails are at different horizontal heights. The body anti-splash target (2) is set on the rail with the higher horizontal height, and the head anti-splash target (1) is set on the rail with the lower horizontal height. The two head anti-splash targets (1), the body anti-splash target (2) and the vacuum chamber are coaxially arranged.

[0008] Furthermore, the cabin splashback target (2) is a two-section structure with the same diameter but different lengths. The cabin splashback target near the interior of the vacuum chamber includes three rings (5), a frame (7) and multiple graphite plates (6). The top of the ring (5) is flat and the bottom is a flat surface with a recess. The three rings (5) are arranged in parallel at equal intervals. Multiple frames are provided at equal intervals between adjacent rings (5). The frame (7) is detachably fixed to the ring by bolts. The graphite plates (6) are detachably fixed to the frame by graphite screws.

[0009] The other section of the cabin splash protection target includes three rings (5), a frame (7) and multiple graphite plates (6). The top of the ring (5) is flat and the bottom is a flat surface with a concave shape. The three rings (5) are arranged in parallel at equal intervals. Multiple frames are arranged at equal intervals between adjacent rings (5). The frame (7) is detachably fixed to the ring by bolts. The graphite plates (6) are detachably fixed to the frame by graphite screws.

[0010] The bottom of the two-section hull splash-proof target is equipped with a movable support with a braking device, which allows it to move freely on the guide rail.

[0011] Furthermore, the head anti-splash target (1) is composed of several anti-splash plates and an annular stainless steel frame. The anti-splash plates are equidistant and fixed at both ends of the annular stainless steel frame at the same angle of inclination as the stainless steel frame. Each anti-splash plate is composed of several graphite plates spliced ​​horizontally. The bottom of the stainless steel frame is provided with a movable bracket with a braking device for free movement on the guide rail.

[0012] Furthermore, the guide rails for placing the chamber splashback target (2) and the docking trolley (3) in the vacuum chamber are the same size, and the guide rails of the chamber splashback target (2) and the docking trolley (3) are seamlessly connected. The bottom of the docking trolley (3) is equipped with a load-bearing wheel with brakes, and the guide rails at the bottom of the docking trolley (3) extend forward.

[0013] A method for preventing splashing during electric propulsion ignition testing, comprising:

[0014] The thruster was placed in the anti-splashing system for electric propulsion ignition test to conduct the electric propulsion ignition test. The graphite plates set on the anti-splashing target (1) on the head and the anti-splashing target (2) on the cabin blocked the splashing products in the electric propulsion ignition test to ensure that the sensitive surface of the vacuum chamber was not affected by the splashing products.

[0015] The beneficial effects of this invention are:

[0016] 1. The electric thruster anti-splash system designed in this invention adopts a modular design. Each module is connected to the vacuum chamber via pulleys. The outlet of the connected pipeline is equipped with a special plug and cap, and the connection lines all adopt double-point double-line design, which ensures the independence of each module. This makes the device proposed in this invention easy to disassemble, transport and maintain between modules, reducing the cost of equipment maintenance and transportation.

[0017] 2. In the system proposed in this invention, both the head anti-splash target and the hull anti-splash target adopt an annular structure, i.e., an inclined structure, to reduce the return of splash products to sensitive surfaces. At the same time, the head anti-splash target and the hull anti-splash target do not require active cooling methods and can withstand at least 360 hours of continuous thrust beam bombardment and at least 120 hours of bombardment from a 5kW electric thruster. Attached Figure Description

[0018] Figure 1 The schematic diagram of the anti-splash system for electric propulsion ignition test provided by the present invention is shown in the figure. In the figure, 1-head anti-splash target, 2-body anti-splash target, 3-docking trolley, 4-vacuum chamber;

[0019] Figure 2 A schematic diagram of the headed anti-splash target provided by the present invention, in which 1-headed anti-splash target, 4-vacuum chamber, 8-rectangular graphite plate;

[0020] Figure 3 A schematic diagram of the installed head anti-splash target provided by the present invention, in which 8 - a rectangular graphite plate;

[0021] Figure 4 and Figure 5 The schematic diagram of the cabin splashback target entering and exiting the vacuum chamber provided by the present invention is shown in the figure. In the figure, 2-cabin splashback target, 3-docking trolley, 4-vacuum chamber;

[0022] Figure 6 A schematic diagram of a splash-proof target for a chamber near the interior of a vacuum chamber provided by the present invention. In the diagram, 5-ring, 6-graphite plate, 7-skeleton;

[0023] Figure 7 Another schematic diagram of the splash-proof target for the cabin provided by the present invention, in which 5-ring, 6-graphite plate, 7-skeleton;

[0024] Figure 8 This is a schematic diagram of the splash-proof target for the docking trolley transport compartment provided by the present invention. Figure 8 In the middle, 2-the hull splash protection target, 3-the docking trolley. Detailed Implementation

[0025] Combination Figure 1-8 This implementation method is described as follows: Figure 1 As shown, the structure of the anti-splash system for electric propulsion ignition testing described in this embodiment includes:

[0026] Two capped splash guard targets 1 are respectively and without spacing set on the two circular surfaces of the cylindrical cabin splash guard target 2, as shown. Figure 2 As shown, the headed splash shield 1 is designed according to the dimensions of the vacuum chamber. After the headed splash shield 1 and the chamber splash shield 2 are combined, the diameter facing the plume direction is 3.2m. The headed splash shield 1 is made of stainless steel and has a movable support at the bottom. The movable support can move freely on the guide rail inside the vacuum chamber. The wheels of the movable support are equipped with brakes. The total height of the movable support is 145mm, the diameter of the large circle is 120mm, the length of the support is 130mm, the width of the support is 130mm, the diameter of the small circle is 90mm, the wheel width of the brake wheel is 80mm, the groove depth is 15mm, the thickness of the support is 9mm, and the movable support has two built-in 6306 bearing steel bearings. There are four mounting holes on the support, the distance between two adjacent mounting holes is 95mm, the diameter of the mounting hole is 13mm, the edge of the large circle is 20mm, and the self-weight of a single mounting target is 6.9kg.

[0027] The end cap splash shield 1 includes a ring-shaped stainless steel frame and several rectangular graphite plates 8. The rectangular graphite plates 8 have a louvered structure, are equidistant, and are fixed at both ends of the ring-shaped stainless steel frame at the same angle to minimize plume interference. Each rectangular graphite plate is fixedly connected to both ends of the stainless steel frame. Each graphite plate is assembled from several 300mm*300mm square graphite plates. The installed end cap splash shield 1 is as follows: Figure 3 As shown, the rear part (3.3m) of the graphite device has a graphite louvered screen at the bottom. To meet the needs of users for different test positions, the bottom graphite screen is movable and its angle is adjustable. The overall louver angle is adjusted by rotating a round steel mechanism.

[0028] The chamber splashback target 2 uses a stainless steel frame with an inner diameter of 3.2m, a length of 7m, and a frame thickness of 80mm. The chamber splashback target 2 has a capacity of 4.5m × 10m. Inside the chamber is a graphite device with an inner diameter of φ3.75m, an outer diameter of φ3.91m, and a total length of 6.5m. The device is divided into front and rear sections; the front section is 3.2m long, and the rear section is 3.3m long. The rear section has a graphite louvered screen at the bottom. A trolley is attached outside the chamber for easy transport. The chamber splashback target is located close to the interior of the vacuum chamber, such as... Figure 6 As shown, it includes three rings 5, a frame 7, and multiple graphite plates 6. The frame 7 has wheels at the bottom and is placed on the internal track for easy access. The lower end of the frame is stepped to avoid the pedestrian track, and the upper part of the rear section avoids the internal equipment. The top of the rings 5 ​​is flat, and the bottom is a flat surface with a recess. The three rings 5 ​​are arranged parallel to each other at equal intervals. Multiple frames are arranged at equal intervals between adjacent rings 5. The frame 7 is detachably fixed to the rings with bolts, and the graphite plates 6 are detachably fixed to the frame with graphite screws. Another section of the cabin splashback target is shown... Figure 7 As shown, it includes three rings 5, a frame 7, and multiple graphite plates 6. The bottom of the rings 5 ​​is a flat surface with a recess. The three rings 5 ​​are arranged in parallel at equal intervals. Multiple frames are arranged at equal intervals between adjacent rings 5. The frames 7 are detachably fixed to the rings with bolts, and the graphite plates 6 are detachably fixed to the frames with graphite screws. The bottom of the two sections of the hull splash shield target is equipped with a movable support with a braking device for free movement on the guide rail. The rings 5 ​​are made of 80mm square steel and are divided into front, middle, and rear rings. The cylindrical body of the graphite plates 6 is 300mm wide, and the bottom screen is 200mm wide.

[0029] In this embodiment, the top of the splashback target near the vacuum chamber is made flat, which facilitates smooth docking of the splashback target and prevents collision with the interior of the vacuum chamber. This method is applicable to vacuum chambers of all sizes.

[0030] The graphite plate 6 measures 500mm x 300mm and has a movable support at the bottom. The trolley is 3.5m long, and its width and height match the internal guide rails for easy connection and transportation. The segmented entry and exit mechanism of the vacuum chamber 5, including the splash-proof target 2, facilitates transport. Figure 4 and Figure 5 As shown.

[0031] The docking trolley 3 is welded from stainless steel square tubing, and its height is the same as that of the gas cylinders on the guide rail inside the chamber. The upper part of the docking trolley 3 has a guide rail of the same size as that inside the vacuum chamber for seamless docking. The docking trolley guide rail extends forward by 300mm to facilitate docking with the guide rail inside the chamber. The bottom of the docking trolley 3 is equipped with load-bearing wheels, each with a load capacity of 1000kg and a brake.

[0032] Both the head-mounted splash guard target 1 and the hull-mounted splash guard target 2 use pressed graphite plates. The graphite plates used in head-mounted splash guard target 1 are 300mm*300mm in size, while those used in hull-mounted splash guard target 2 are 500mm*300mm in size. The total area of ​​the graphite plates is approximately 120 square meters. The docking trolley transports the hull-mounted splash guard targets as follows: Figure 8 As shown.

[0033] During the docking process of the head splash shield 1 and the hull splash shield 2, the outlet of the docking pipeline is equipped with a dedicated plug and cap, and the connection lines all adopt a double-point double-line configuration. The head splash shield 1, the hull splash shield 2, and the docking trolley 3 are all equipped with dedicated packaging boxes to facilitate equipment transportation. In the electric propulsion ignition test splash shield system, frequently calibrated and replaced components are placed in easily replaceable positions to facilitate component replacement and calibration. When the installation inside the hull is completed, the graphite plate and the container are concentrically positioned, with the bottom placed on the hull guide rail via bottom wheels, parallel to the bottom guide rail. The front end of the graphite plate is 3.5m away from the container flange face. The graphite plate is tangentially connected and covers the cylindrical frame, and is distributed in a louvered manner at the bottom.

[0034] During electric propulsion ignition tests, the main power supply of the electric propulsion ignition test splashproof system is a standard 220V interface, clearly marked and equipped with a switch indicator light. The electric propulsion ignition test splashproof system is externally grounded, with the power ground connected to the shell ground. The flow meter is equipped with a separate power switch and indicator light. The communication interface of the electric propulsion ignition test splashproof system is an RS232 connection, integrated into an aviation plug. All structures of the electric propulsion ignition test splashproof system have compatibility and scalability.

[0035] After completing the above system design, this embodiment also provides a method for preventing splashing during electric propulsion ignition testing, as follows:

[0036] Step 1: Set the brake wheel of one of the end cap sputtering targets 1 to the brake state, place the end cap sputtering target 1 on the docking trolley 3, control the docking trolley 3 to move until the docking trolley 3 is in complete contact with the vacuum chamber 4, so that the end cap sputtering target 1 enters the vacuum chamber 4. At the same time, set the brake wheel of the end cap sputtering target 1 to the moving state, control the end cap sputtering target 1 to move on the guide rail of the vacuum chamber 4 until it reaches the end of the vacuum chamber 4.

[0037] Step 2: Set the brake wheel of the front compartment splash shield target 2 to the brake state, and place the front compartment splash shield target 2 on the docking trolley 3. Control the docking trolley 3 to move until the docking trolley 3 is in complete contact with the vacuum chamber 4, so that the front compartment splash shield target 2 enters the slide rail of the vacuum chamber 4. At the same time, set the brake wheel of the front compartment splash shield target 2 to the moving state, and control the front compartment splash shield target 2 to move on the guide rail of the vacuum chamber 4 until it docks with the head splash shield target 1.

[0038] Step 3: Replace the front part of the cabin splashback target 2 in Step 2 with the rear part of the cabin splashback target 2, and repeat Step 2 until the rear part of the cabin splashback target 2 and the front part of the cabin splashback target 2 are docked.

[0039] Step 4: Place the thruster into the vacuum chamber 4, replace the head sputtering target 1 in Step 1 with another head sputtering target 1, and repeat Step 1 until the other head sputtering target 1 and the rear chamber sputtering target 2 are docked. After docking, conduct an electric propulsion ignition test. The graphite plates set on the head sputtering target 1 and the chamber sputtering target 2 block the sputtering products in the electric propulsion ignition test to ensure that the sensitive surface of the vacuum chamber is not affected by sputtering products.

[0040] In the electric propulsion ignition experiment, the specific tests of each component included:

[0041] Verification pressure requirements: Pressure-bearing components in the equipment must undergo a verification pressure test at 1.5 times the corresponding working pressure, and the burst pressure must be no less than 2 times the working pressure.

[0042] Overvoltage and overcurrent protection: The system power supply is designed with overvoltage and overcurrent protection measures. The AC input is protected by double fuses, and the switch is also designed with double switching of neutral and live wires.

[0043] Safety protection: The system has sufficient safety features to ensure the safety of users. Accessible parts with a voltage to ground (AC peak-to-peak or DC) higher than 36V are protected against damage.

[0044] Insulation: Under standard atmospheric conditions, the insulation resistance between the 220V power supply and the chassis should be greater than 20MΩ. The entire system should be reliably grounded, with a grounding resistance of less than 1Ω. Grounding protection point: The entire system should be reliably grounded at a single point.

[0045] Cleanliness requirements: Appropriate measures for controlling foreign matter and cleanliness must be taken during the development process. Operators must wear clean, powder-free gloves, paying particular attention to pipe connections and avoiding direct hand contact. The entire system must undergo and pass a 120-hour aging test. Software interlocking ensures that no vacuum accidents will occur. The system can be set with a pressure protection point; if the system detects that the pressure exceeds the protection point, the protection procedure will be activated (except for cases of human exposure to the atmosphere).

[0046] Performance verification: The sensitive surface was observed after 360 hours of continuous thrust beam bombardment, and the sensitive surface was not affected by sputtering products.

[0047] After verification through the above experiments, it can be concluded that the anti-splash system for electric propulsion ignition test provided by the present invention can withstand the thruster beam bombardment for no less than 360 hours without the need for active cooling. In addition, it was bombarded by a 5kW electric thruster for no less than 120 hours during the test, which further verified the system performance and all met the design requirements.

[0048] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent substitutions, and improvements made to the above embodiments without departing from the scope of the present invention, based on the technical essence of the present invention and within the spirit and principles of the present invention, shall still fall within the protection scope of the present invention.

Claims

1. A splash protection system for electric propulsion ignition testing, characterized in that, include: Two headed anti-splash targets (1) and a body anti-splash target (2) are installed inside the vacuum chamber. The two headed anti-splash targets (1) are respectively installed on both sides of the body anti-splash target (2) without any gap. The anti-splash system for electric propulsion ignition test also includes two sets of parallel support rails for the head anti-splash target (1) and the body anti-splash target (2) installed in the vacuum chamber. The two sets of rails are at different horizontal heights. The body anti-splash target (2) is installed on the rail with the higher horizontal height, and the head anti-splash target (1) is installed on the rail with the lower horizontal height. The two head anti-splash targets (1), the body anti-splash target (2) and the vacuum chamber are coaxially arranged. The cabin splashback target (2) is a two-section structure with the same diameter but different lengths. The cabin splashback target near the vacuum chamber includes three rings (5), a frame (7) and multiple graphite plates (6). The top of the ring (5) is flat and the bottom is a flat surface with a depression. The three rings (5) are arranged in parallel at equal intervals. Multiple frames are provided at equal intervals between adjacent rings (5). The frame (7) is detachably fixed to the ring by bolts. The graphite plates (6) are detachably fixed to the frame by graphite screws. The other section of the cabin splash protection target includes three rings (5), a frame (7) and multiple graphite plates (6). The top of the ring (5) is flat and the bottom is a flat surface with a concave shape. The three rings (5) are arranged in parallel at equal intervals. Multiple frames are arranged at equal intervals between adjacent rings (5). The frame (7) is detachably fixed to the ring by bolts. The graphite plates (6) are detachably fixed to the frame by graphite screws. The bottom of the two-section hull splash-proof target is equipped with a movable support with a braking device, which allows it to move freely on the guide rail; The head anti-splash target (1) consists of several anti-splash plates and an annular stainless steel frame. The anti-splash plates are equidistant and fixed at both ends of the annular stainless steel frame at the same angle of inclination as the stainless steel frame. Each anti-splash plate is composed of several graphite plates spliced ​​horizontally. The bottom of the stainless steel frame is provided with a movable bracket with a braking device for free movement on the guide rail.

2. The anti-splash system for electric propulsion ignition testing according to claim 1, characterized in that, The guide rails for placing the splash shield target (2) in the vacuum chamber and the guide rails for docking trolley (3) are the same size. The guide rails of the splash shield target (2) and the guide rails of the docking trolley (3) are seamlessly connected. The bottom of the docking trolley (3) is equipped with a load-bearing wheel with brakes, and the guide rails at the bottom of the docking trolley (3) extend forward.

3. A method for preventing splashing during electric propulsion ignition testing, applied to the anti-splashing system for electric propulsion ignition testing as described in any one of claims 1-2, characterized in that, include: The thruster was placed in the anti-splashing system for electric propulsion ignition test to conduct the electric propulsion ignition test. The graphite plates set on the anti-splashing target (1) on the head and the anti-splashing target (2) on the cabin blocked the splashing products in the electric propulsion ignition test to ensure that the sensitive surface of the vacuum chamber was not affected by the splashing products.

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