Satellite cryogenic propellant liquid injection and storage combined device

Abstract

The invention relates to the technical field of space propellant fluid, in particular to a satellite low-temperature propellant liquid injection and storage combined device which comprises a radial injector, parallel channels, a liquid collector and a channel distributor, the radial injector is of a thin-wall cylinder structure, and the middle line of the radial injector coincides with the inner axial direction of a low-temperature storage box; the liquid collector is arranged at the lower end of the radial ejector, is welded and fixed with the bottom end of the radial ejector, and is communicated with a liquid opening of the low-temperature storage tank; the channel distributor is arranged at the upper end of the radial ejector, is welded and fixed with the top end of the radial ejector, and is communicated with an air port of the low-temperature storage tank; the top end of each parallel channel is fixedly welded to the channel distributor, and the bottom end of each parallel channel is fixedly welded to the liquid collector. The fluid storage and mixing efficiency under the space microgravity condition is achieved to the maximum extent, thermal stratification in the low-temperature storage tank is effectively eliminated through sufficient convection mixing, and the temperature uniformity in the storage tank is improved.

Description

Technical Field

[0001] The present application relates to the field of space propellant fluid technology, and in particular to a satellite cryogenic propellant liquid injection and storage combined device. Background Art

[0002] In the field of aerospace vehicle propulsion technology, due to the technical advantages of cryogenic propellants such as high-density storage, high structural efficiency of tanks, and on-orbit refueling, cryogenic propellants will gradually replace normal temperature propellants in the future and be widely used in space satellites, spacecraft, orbital spacecraft and other spacecraft. The application of cryogenic propellants can make the propulsion system smaller and lighter, and increase the service life of the spacecraft.

[0003] Due to the influence of microgravity conditions, the propellant inside the cryogenic tank of space cryogenic propellant will produce thermal stratification and pressure stratification with obvious temperature gradient, which will lead to abnormal increase of local pressure. The tank safety is forced to open and the gas-liquid mixing will cause propellant loss and reduce the service life of the spacecraft. Summary of the invention

[0004] The present application provides a satellite cryogenic propellant liquid injection and storage combined device, which minimizes the problem of cryogenic propellant thermal stratification and meets the temperature and pressure control requirements of aerospace cryogenic propellant tanks.

[0005] In order to achieve the above-mentioned purpose, the present application provides a satellite cryogenic propellant liquid injection and retention combination device, which is arranged inside a cryogenic tank, and includes a radial injector, parallel channels, a liquid collector and a channel distributor, wherein: the radial injector is a thin-walled cylindrical structure, the midline of which coincides with the axial direction inside the cryogenic tank, and the coaxiality of the two is ≤0.05mm; the liquid collector is arranged at the lower end of the radial injector, welded and fixed to the bottom end of the radial injector, and connected to the liquid port of the cryogenic tank; the channel distributor is arranged at the upper end of the radial injector, welded and fixed to the top end of the radial injector, and connected to the gas port of the cryogenic tank; a plurality of parallel channels are arranged, and the top end of each parallel channel is welded and fixed to the channel distributor, and the bottom end is welded and fixed to the liquid collector.

[0006] Furthermore, the inner diameter of the radial injector is 6-20 mm, the wall thickness of the cylinder is 2-5 mm, and the height is 40%-80% of the height of the cryogenic storage tank.

[0007] Furthermore, a plurality of injection holes are evenly distributed along the axial direction of the radial injector, and the number of the injection holes is the same as the number of the parallel channels; the inner diameter of the injection holes is 0.5-3 mm, and the hole spacing is 5%-10% of the height of the low-temperature storage tank.

[0008] Further, the direction of the normal line of the injection hole of the radial injector cylinder cross section is in the same plane as the parallel channel.

[0009] Furthermore, each parallel channel is welded by a screen and a titanium alloy frame, and the distance between the screen and the inner wall of the cryogenic storage tank is 2-9 mm.

[0010] Furthermore, the liquid collector is an ultra-thin-wall cylindrical structure, and its volume is ≥ twice the internal volume of the parallel channels.

[0011] Furthermore, the number of the parallel channels is an even number; the structural parameters of the parallel channels are determined by calculating the total flow resistance of the propellant inside the cryogenic tank.

[0012] Furthermore, the radial injector, the parallel channel, the liquid collector and the channel distributor are all made of titanium alloy.

[0013] The present application provides a satellite cryogenic propellant liquid injection and storage combined device, which has the following beneficial effects:

[0014] On the premise of meeting technical indicators such as the weight and overall dimensions of the cryogenic storage tank, the present application maximizes the fluid retention and mixing efficiency under space microgravity conditions, effectively eliminates thermal stratification in the cryogenic storage tank through sufficient convection mixing, and improves the temperature uniformity inside the storage tank; multiple parallel channels are arranged to have a good fluid retention function; the normal line of the radial injector's injection hole is directly facing each channel, ensuring sufficient mixing of the cryogenic liquid, and adopts variable-speed radial injection mixing to ensure strong convection mixing without dead corners in the internal space of the cryogenic storage tank; after injection, the liquid adheres to the channel under the action of surface tension, further improving the overall retention capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings constituting a part of this application are used to provide a further understanding of this application, so that other features, purposes and advantages of this application become more obvious. The schematic embodiment drawings and their descriptions of this application are used to explain this application and do not constitute an improper limitation on this application. In the drawings:

[0016] Figure 1 This is a front view of a satellite cryogenic propellant liquid injection and storage combined device provided according to an embodiment of the present application;

[0017] Figure 2 It is a schematic diagram of the flow of fluid in a satellite cryogenic propellant liquid injection and storage combination device provided in an embodiment of the present application;

[0018] In the figure: 1- radial injector, 11- injection hole, 2- parallel channel, 21- screen, 22- titanium alloy skeleton, 3- liquid collector, 4- channel distributor. DETAILED DESCRIPTION

[0019] In order 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 in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this application.

[0020] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0021] In the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0022] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.

[0023] In addition, the term "plurality" shall mean two or more.

[0024] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0025] like Figure 1As shown, the present application provides a satellite cryogenic propellant liquid injection and retention combined device, which is arranged inside a cryogenic tank, and includes a radial injector 1, a parallel channel 2, a liquid collector 3 and a channel distributor 4, wherein: the radial injector 1 is a thin-walled cylindrical structure, the midline of which coincides with the axial direction inside the cryogenic tank, and the coaxiality of the two is ≤0.05mm; the liquid collector 3 is arranged at the lower end of the radial injector 1, is welded and fixed to the bottom end of the radial injector 1, and is connected to the liquid port of the cryogenic tank; the channel distributor 4 is arranged at the upper end of the radial injector 1, is welded and fixed to the top end of the radial injector 1, and is connected to the gas port of the cryogenic tank; a plurality of parallel channels 2 are arranged, and the top end of each parallel channel 2 is welded and fixed to the channel distributor 4, and the bottom end is welded and fixed to the liquid collector 3.

[0026] Specifically, under the conditions of microgravity in space, the cryogenic tank will have uncertain gas-liquid positions, random distribution of gas-liquid two-phase flow, parallel gasification and liquefaction, and thermal stratification and pressure stratification with obvious temperature gradient, which will lead to the problem of gas-liquid mixing caused by abnormal pressure and safe decompression, which will cause propellant loss and reduce the service life of the spacecraft. The satellite cryogenic propellant liquid injection and storage combined device provided in the embodiment of the present application is based on the professional coupling optimization design of space fluid mechanics, engineering thermodynamics, materials science, structural statics and dynamics, etc., to maximize the fluid retention and mixing efficiency under the conditions of microgravity in space, and effectively eliminate the thermal stratification in the cryogenic tank through sufficient convection mixing, thereby improving the temperature uniformity inside the tank. The device is arranged as a whole inside a cryogenic storage tank, wherein the radial injector 1 is a high-precision structural component used as a fluid guide, a fluid radially and highly uniformly sprayed component, and can also play a role of fixing and supporting the entire device; the liquid collector 3 is arranged at the lower end of the radial injector 1, and is used to store the sprayed liquid, and is connected to the liquid port of the cryogenic storage tank to play a role of connection and fixing; the channel distributor 4 is arranged at the upper end of the radial injector 1, and is used for welding and fixing multiple parallel channels 2, and is connected to the air port of the storage tank to achieve the fixation of the air port of the storage tank; multiple parallel channels 2 are arranged, and the top end of each parallel channel 2 is welded and fixed to the channel distributor 4, and the bottom end is welded and fixed to the liquid collector 3. Liquid propellant is retained by surface tension, thereby improving sufficient convective mixing and continuous retention of the retained liquid and the sprayed supercooled liquid, so that the retained liquid enters the liquid collector 3 through the parallel channel 2 to replenish the propellant for the liquid collector 3.

[0027] Further, the inner diameter of the radial injector 1 is 6-20 mm, the wall thickness of its cylinder is 2-5 mm, and its height is 40%-80% of the height of the cryogenic tank. The cryogenic tank as a whole is a cylindrical structure of a spherical short column segment, and the volume is preferably 65 liters. The radial injector 1 is arranged in the middle position of the cryogenic tank, and the center line coincides with the axial direction of the cryogenic tank, and the coaxiality of the two is not greater than 0.05 mm. In the embodiment of the present application, the inner diameter of the radial injector 1 is preferably 10 mm, the wall thickness of its inner cylinder is preferably 2.5 mm, and the height is preferably 68% of the height of the cryogenic tank.

[0028] Furthermore, a plurality of injection holes 11 are evenly distributed along the axial direction of the radial injector 1, and the number of the injection holes 11 is the same as the number of the parallel channels 2; the inner diameter of the injection holes 11 is 0.5-3 mm, and the hole spacing is 5%-10% of the height of the cryogenic storage tank.

[0029] Furthermore, the direction of the normal line of the injection hole 11 of the cylindrical cross section of the radial injector 1 is in the same plane as the parallel channel 2 .

[0030] Specifically, a plurality of injection holes 11 are evenly distributed along the axial direction of the radial injector 1, the direction of the normal of the injection hole 11 in the cylindrical cross section of the radial injector 1 is in the same plane as the parallel channel 2, and the number of the injection holes 11 is the same as the number of the parallel channels 2; in the embodiment of the present application, the number of the injection holes 11 is preferably 4, the inner diameter of the injection hole 11 is preferably 2 mm, and the hole spacing is preferably 9% of the height of the cryogenic storage tank.

[0031] Furthermore, each parallel channel 2 is welded by a mesh 21 and a titanium alloy frame 22, and the distance between the parallel channel 2 and the inner wall of the cryogenic storage tank is 2-9 mm. In the embodiment of the present application, the parallel channel 2 is a structure obtained by welding the mesh 21 and a titanium alloy frame 22 with a rectangular cross-section, and the distance between the parallel channel 2 and the inner wall of the cryogenic storage tank is preferably 5.5 mm, and the tolerance of the distance between the entire channel and the inner wall is not greater than 0.3 mm.

[0032] Furthermore, the liquid collector 3 is an ultra-thin-wall cylindrical structure, and its volume is ≥ twice the internal volume of the parallel channel 2. The diameter of the liquid collector 3 is preferably 150 mm, the height is preferably 180 mm, and the volume is preferably 3.5 L. According to actual conditions, a cassette filter is also provided inside the liquid collector 3.

[0033] Furthermore, the number of parallel channels 2 is an even number; the structural parameters of the parallel channels 2 are calculated and determined based on the total flow resistance of the propellant inside the cryogenic storage tank. The number of parallel channels 2 is generally an even number, and the top of each parallel channel 2 is plug-welded to the channel distributor 4 through a slot, and the bottom is welded and fixed to the liquid collector 3. Depending on the number, the angles between the parallel channels 2 are different, and the whole is evenly distributed between the channel distributor 4 and the liquid collector 3; when the number of parallel channels 2 is 4, the angle of the evenly distributed channels is 90°, when the number of parallel channels 2 is 6, the angle of the evenly distributed channels is 60°, and when the number of parallel channels 2 is 8, the angle of the evenly distributed channels is 45°. In the embodiment of the present application, the number of parallel channels 2 is preferably 4. Based on the total flow resistance of the propellant inside the cryogenic storage tank, the width of the parallel channels 2 is preferably 30 mm, the cross-sectional height is 10 mm, and the cross-sectional area is 300 mm 2 .

[0034] Furthermore, the radial injector 1, the parallel channel 2, the liquid collector 3 and the channel distributor 4 are all made of titanium alloy. In the embodiment of the present application, the radial injector 1, the parallel channel 2, the liquid collector 3 and the channel distributor 4 are all made of TC4 titanium alloy, and the device as a whole is a full titanium alloy electron beam welded structure. During the welding process, welding positioning tooling welding and heat treatment positioning tooling stress relief annealing are used, which has technical advantages such as high strength, high rigidity, low weight, high structural dimensional accuracy, high shape and position dimensional accuracy, and high reliability.

[0035] Specifically, Figure 2 As shown, the satellite cryogenic propellant liquid injection and storage combination device provided in the embodiment of the present application is arranged inside the tank, and its parallel channel 2 and the inner wall of the tank will form a liquid belt with a triangular cross-section. Under the microgravity conditions in space, surface tension (viscous force) plays a dominant role, and the propellant liquid will automatically accumulate on the channel surface; when working, the propellant liquid in the liquid collector 3 is extracted by a cryogenic pump, and the propellant liquid enters the radial injector 1 through the liquid inverting pipe. The radial injector 1 sprays the propellant liquid outward, and the propellant liquid after injection will be retained for a period of time, and finally enter the parallel channel 2, and return to the liquid collector 3 through the parallel channel 2 again, forming a recycling of the propellant liquid, which maximizes the efficiency of fluid retention and mixing under the microgravity conditions in space.

[0036] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A satellite cryogenic propellant liquid injection and storage combined device, arranged inside a cryogenic tank, characterized in that: It includes radial injectors, parallel channels, liquid collectors and channel distributors, wherein: The radial injector is a thin-walled cylindrical structure, the center line of which coincides with the inner axial line of the cryogenic storage tank, and the coaxiality of the two is ≤0.05mm; The liquid collector is arranged at the lower end of the radial injector, is welded and fixed to the bottom end of the radial injector, and is communicated with the liquid port of the cryogenic storage tank; The channel distributor is arranged at the upper end of the radial injector, is welded and fixed to the top end of the radial injector, and is communicated with the gas port of the cryogenic storage tank; A plurality of parallel channels are provided, and the top end of each parallel channel is welded and fixed to the channel distributor, and the bottom end is welded and fixed to the liquid collector.

2. The satellite cryogenic propellant liquid injection and storage combined device according to claim 1, characterized in that: The inner diameter of the radial injector is 6-20 mm, the wall thickness of the cylinder is 2-5 mm, and the height is 40%-80% of the height of the cryogenic storage tank.

3. The satellite cryogenic propellant liquid injection and storage combined device according to claim 2, characterized in that: A plurality of injection holes are evenly distributed along the axial direction of the radial injector, and the number of the injection holes is the same as the number of the parallel channels; the inner diameter of the injection holes is 0.5-3 mm, and the hole spacing is 5%-10% of the height of the low-temperature storage tank.

4. The satellite cryogenic propellant liquid injection and storage combined device according to claim 3, characterized in that: The direction of the normal line of the injection hole of the radial injector cylinder cross section is in the same plane as the parallel channel.

5. The satellite cryogenic propellant liquid injection and storage combined device according to claim 4, characterized in that: Each of the parallel channels is welded by a screen and a titanium alloy frame, and the distance between the parallel channel and the inner wall of the low-temperature storage tank is 2-9 mm.

6. The satellite cryogenic propellant liquid injection and storage combined device according to claim 5, characterized in that: The liquid collector is an ultra-thin-wall cylindrical structure, and its volume is ≥ twice the internal volume of the parallel channels.

7. The satellite cryogenic propellant liquid injection and storage combined device according to claim 6, characterized in that: The number of the parallel channels is an even number; the structural parameters of the parallel channels are determined by calculating the total flow resistance of the propellant inside the cryogenic tank.

8. The satellite cryogenic propellant liquid injection and storage combined device according to claim 7, characterized in that: The radial injector, the parallel channel, the liquid collector and the channel distributor are all made of titanium alloy.

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