Fluid medium injection method and device

Abstract

The invention discloses a fluid medium injection method and device, and belongs to the technical field of fluid medium conveying. A plurality of injection points are arranged in the circumferential direction of an injection opening of a to-be-filled cavity, a fluid medium is injected into the to-be-filled cavity along the injection points, and the fluid medium pressure of at least one injection point is higher than that of the other injection points. The fluid medium entering the to-be-filled cavity forms circumferential sweeping flow along the filling cavity under the action of the circumferential pressure difference; according to the method, the fluid medium pressure of at least one injection point is set to be higher than the fluid medium pressure of the other injection points, so that a non-equilibrium pressure field distributed in the circumferential direction can be constructed in the to-be-filled cavity, and static pressure balance formed under the condition of multiple injection points is destroyed; therefore, the fluid medium entering the to-be-filled cavity forms circumferential sweeping flow along the to-be-filled cavity under the action of the circumferential pressure difference, and the fluid medium can cover and fully fill the to-be-filled cavity in a continuous flowing state.

Description

Technical Field

[0001] This invention relates to the field of fluid medium transportation technology, and in particular to a method and apparatus for injecting fluid medium. Background Technology

[0002] For complex cavities, due to the complex geometric structure inside the cavity, there are technical problems such as dead zones or blind ends that are difficult to be completely filled by the medium during fluid injection, or sudden changes in the inner diameter that cause gas vortices or low-pressure zones to form during the medium injection, resulting in air being trapped inside the cavity and unable to be discharged.

[0003] Taking the casing of a solid rocket motor as an example, its fluid medium is propellant, which has the characteristics of high viscosity and high yield stress. Because the casing has a raised structure higher than the overflow groove, the existing technology usually uses the same or similar pressure conditions to inject the propellant axially at multiple points. When the propellant is injected into the inner cavity of the casing, the raised structure of the inner cavity will seriously affect the filling efficiency of the propellant. That is, in the area of ​​the raised structure higher than the overflow groove, the propellant lacks effective driving force and it is difficult to squeeze out the gas there. In other words, the main flow direction of the propellant injected into the casing in this way is along the axial direction of the casing, and the flow mode is relatively simple. Therefore, some gas will remain in the dead zone or blind end, resulting in defects such as insufficient filling, local stagnation or cavitation.

[0004] To address the aforementioned problems, this invention provides a method and apparatus for injecting a fluid medium, thereby resolving the technical issues of insufficient filling, localized stagnation, or voids that exist in the prior art during the filling of complex cavities with a fluid medium. Summary of the Invention

[0005] This invention provides a method and apparatus for injecting a fluid medium to solve the technical problems of insufficient filling, local stagnation, or voids that exist in the prior art during the filling of complex cavities with a fluid medium.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: This invention provides a method for injecting a fluid medium into a cavity to be filled. The method includes the following steps: Multiple injection points are arranged circumferentially along the injection port of the cavity to be filled. The fluid medium is injected into the cavity to be filled along the injection points, and the fluid medium pressure at at least one injection point is higher than the fluid medium pressure at the other injection points, so that the fluid medium entering the cavity to be filled forms a circumferential sweeping flow along the cavity under the action of the circumferential pressure difference.

[0007] Furthermore, the injection point with the highest fluid medium injection pressure is called the high-pressure injection point, and the other injection points are called low-pressure injection points. The fluid medium injection pressure at the high-pressure injection point is not lower than 0.3 MPa.

[0008] Furthermore, the injection pressure of the fluid medium located at the low-pressure injection point is not higher than 10 kPa.

[0009] Furthermore, it also includes adjusting the fluid medium injection pressure at the injection point to change the positions of the high-pressure injection point and the low-pressure injection point.

[0010] Furthermore, the fluid medium injection pressure at the injection point remains unchanged.

[0011] Furthermore, the number of high-pressure injection points is one during the initial stage of fluid medium injection. During the fluid medium injection process, the number of high-pressure injection points increases as the fluid medium injection time increases. The number of high-pressure injection points increases by adjusting the low-pressure injection points adjacent to the high-pressure injection points sequentially as high-pressure injection points along the circumference of the injection port of the cavity to be filled in a clockwise or counterclockwise direction. or, During the injection of the fluid medium, the number of high-pressure injection points remains constant, while the position of the high-pressure injection points changes as the fluid medium injection time increases. The position of the high-pressure injection points changes in the following manner: Along the circumference of the injection port of the cavity to be filled, in a clockwise or counterclockwise direction, the low-pressure injection point adjacent to the high-pressure injection point is sequentially adjusted to become the high-pressure injection point, while the original high-pressure injection point is adjusted to become the low-pressure injection point.

[0012] Furthermore, the number of high-pressure injection points is multiple during the initial stage of fluid medium injection, and there is at least one low-pressure injection point between any two adjacent high-pressure injection points; The number of high-pressure injection points and low-pressure injection points remains unchanged, and the positions of the high-pressure injection points and low-pressure injection points are adjusted according to a set time interval, so as to form a circumferential non-equilibrium pressure field that varies with time in the cavity to be filled. or, When there are at least two low-pressure injection points between adjacent high-pressure injection points, the number of high-pressure injection points and the number of low-pressure injection points change, and the number of high-pressure injection points increases by one or more at a set time interval.

[0013] Furthermore, the pressure difference between the fluid medium injection point and the low-pressure injection point is not less than 0.1 MPa.

[0014] A fluid medium injection device for injecting a fluid medium into a cavity to be filled, comprising: Multiple injection branches for circumferential multi-point injection into the cavity to be filled; A flow regulating device is provided on each of the injection branches; A control device communicatively connected to the flow regulating device, the control device being used to control the opening degree of the flow regulating device so that the injection pressure at at least one injection point is different from the injection pressure at the other injection points, so as to control the fluid medium entering the cavity to be filled to form a circumferential sweeping flow along the filling cavity under the action of the circumferential pressure difference.

[0015] Furthermore, it also includes an injection main pipe, with the injection branch pipes connected to one end of the injection main pipe, and the injection branch pipes are evenly distributed along the circumference of the injection main pipe.

[0016] Compared with the prior art, the technical solution disclosed in this invention has the following beneficial effects: The present invention sets the fluid medium pressure at at least one injection point to be higher than that at the other injection points, which can create a non-equilibrium pressure field distributed circumferentially in the cavity to be filled, thereby disrupting the static pressure balance formed under the condition of multiple injection points. This allows the fluid medium entering the cavity to be filled to form a circumferential sweeping flow along the filling cavity under the action of the circumferential pressure difference, so that the fluid medium can cover and fully fill the cavity to be filled in a continuous flow state. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of the fluid medium injection device in an embodiment of the present invention; Figure 2 for Figure 1 A structural diagram from another perspective; Figure 3 This is a schematic diagram of the structure of the fluid medium injection device installed inside the housing in an embodiment of the present invention.

[0019] The components are: 1. Injection branch pipe; 2. Flow regulating device; 3. Injection main pipe; 4. Shell. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] This invention provides a method and apparatus for injecting fluid media, which can solve the technical problems of insufficient filling, local stagnation or voids during the filling of complex cavities by fluid media in the prior art.

[0023] The present invention provides a method for injecting a fluid medium into a cavity to be filled. The method includes the steps of: arranging a plurality of injection points circumferentially along the injection port of the cavity to be filled; injecting the fluid medium into the cavity to be filled along the injection points; and ensuring that the fluid medium pressure at at least one injection point is higher than the fluid medium pressure at the other injection points, so that the fluid medium entering the cavity to be filled forms a circumferential sweeping flow along the cavity under the action of the circumferential pressure difference.

[0024] When there is a complex geometric structure in the cavity to be injected, it is difficult to completely fill the dead zone or blind end of the cavity during the injection process, resulting in air being trapped inside the cavity and unable to be discharged. In this embodiment, the fluid medium pressure at at least one injection point is set higher than that at the other injection points. This can create a non-equilibrium pressure field distributed circumferentially in the cavity to be filled, which can disrupt the static pressure balance formed under the condition of multiple injection points. This allows the fluid medium entering the cavity to form a circumferential sweeping flow along the filling cavity under the action of the circumferential pressure difference. This allows the fluid medium to cover and fully fill the cavity to be filled in a continuous flow state, thereby effectively improving the filling efficiency of the fluid medium.

[0025] In this embodiment, the injection point with the highest fluid medium injection pressure is defined as the high-pressure injection point, and the other injection points are defined as low-pressure injection points. The fluid medium injection pressure at the high-pressure injection point is not lower than 0.3 MPa, while the fluid medium injection pressure at the low-pressure injection point is not higher than 10 kPa. Those skilled in the art will understand that the injection pressure at the high-pressure injection point and the injection pressure at the low-pressure injection point are not limited to the above-mentioned ranges. Relevant practitioners can reasonably set the injection pressure according to the specific structure of the cavity to be filled and the type of fluid medium.

[0026] This embodiment also includes adjusting the fluid medium injection pressure at the injection point to change the positions of the high-pressure injection point and the low-pressure injection point; the purpose of changing the positions of the high-pressure injection point and the low-pressure injection point is to change the flow inertia of the fluid medium in the cavity to be filled, and further disrupt the static pressure balance formed by the fluid medium.

[0027] The number of selectable high-pressure injection points is set to one in the initial stage of fluid medium injection. This embodiment provides the following two methods for adjusting the high-pressure injection point and the low-pressure injection point as a reference: During the fluid medium injection process, the number of high-pressure injection points increases with the extension of the fluid medium injection time. The method of increasing the number of high-pressure injection points is as follows: along the circumference of the injection port of the cavity to be filled, in a clockwise or counterclockwise direction, the low-pressure injection points adjacent to the high-pressure injection points are sequentially adjusted to high-pressure injection points. Taking six injection points as an example, as the fluid medium injection time extends, the number of high-pressure injection points gradually increases from one to six in a clockwise direction, while the corresponding low-pressure injection points gradually decrease from five to zero. The rate of increase of high-pressure injection points can be defined according to the maximum volume of the cavity to be filled. When the injection volume is within one-sixth of the maximum volume of the cavity to be filled, one high-pressure injection point is set; when the injection volume is between one-sixth and two-sixths of the maximum volume of the cavity to be filled, two high-pressure injection points are added, and high-pressure injection points are added one by one according to the injection volume. In this invention, relevant practitioners can reasonably set the reference standard for increasing high-pressure injection points and the number of high-pressure injection points that can be added each time according to the actual situation.

[0028] During the fluid medium injection process, the number of high-pressure injection points remains constant, while the positions of the high-pressure injection points change as the fluid medium injection time increases. The method for changing the position of the high-pressure injection points is as follows: along the circumference of the injection port of the cavity to be filled, in a clockwise or counterclockwise direction, the low-pressure injection points adjacent to the high-pressure injection points are sequentially adjusted to high-pressure injection points, while the original high-pressure injection points are adjusted to low-pressure injection points. Similarly, taking six injection points as an example, as the fluid medium injection time increases, the position of the high-pressure injection points transitions clockwise from the first to the sixth, while the number of five low-pressure injection points remains constant. The adjustment speed of the high-pressure injection point position can be defined based on the maximum volume of the cavity to be filled. When the injection volume is within one-sixth of the maximum volume of the cavity to be filled, one injection point is set as a high-pressure injection point. When the injection volume is between one-sixth and two-sixths of the maximum volume of the cavity to be filled, the high-pressure injection point is changed to the second adjacent injection point, and the original high-pressure injection point is adjusted to a low-pressure injection point. Those skilled in the art can reasonably set the adjustment speed of the high-pressure injection point position according to the actual situation.

[0029] The number of selectable high-pressure injection points is set to multiple during the initial stage of fluid medium injection, and there is at least one low-pressure injection point between any two adjacent high-pressure injection points. This embodiment provides the following two methods for adjusting the high-pressure and low-pressure injection points as a reference, as follows: The number of high-pressure injection points and low-pressure injection points remains unchanged, and the positions of the high-pressure injection points and low-pressure injection points are adjusted according to a set time interval to form a circumferential non-equilibrium pressure field that changes with time in the cavity to be filled; during the adjustment of the position of the high-pressure injection points, it is always ensured that there is at least one low-pressure injection point between two adjacent high-pressure injection points.

[0030] When there are at least two low-pressure injection points between adjacent high-pressure injection points, the number of high-pressure injection points and low-pressure injection points changes, and the number of high-pressure injection points increases by one or more at set time intervals. It should be noted that there must be at least one low-pressure injection point between each newly added high-pressure injection point and an adjacent original high-pressure injection point. At the same time, when there are at least two newly added high-pressure injection points, the condition that there is at least one low-pressure injection point between adjacent high-pressure injection points is also met.

[0031] In this embodiment, the injection pressure of the fluid medium at the injection point remains unchanged, that is, the injection pressure of the fluid medium is not adjusted during the injection of the fluid medium into the cavity to be filled; similarly, taking six injection points as an example, 1-5 high-pressure injection points can be set, and the remaining injection points are set as low-pressure injection points, and the fluid medium is injected in this arrangement; it should be noted that at least one low-pressure injection point needs to be reserved when using this method.

[0032] In this embodiment, the pressure difference between the high-pressure injection point and the low-pressure injection point is not less than 0.1 MPa; relevant practitioners can set the injection pressure difference of the fluid medium according to the actual situation.

[0033] refer to Figures 1 to 2This invention provides a fluid medium injection device in embodiment two, used to inject fluid medium into a cavity to be filled. The device includes: multiple injection branch pipes 1 for circumferential multi-point injection into the cavity; a flow regulating device 2 disposed on each injection branch pipe 1; and a control device communicatively connected to the flow regulating device 2, the control device controlling the opening degree of the flow regulating device 2 so that the injection pressure at at least one injection point is different from the injection pressure at the other injection points, thereby controlling the fluid medium entering the cavity to form a circumferential sweeping flow along the cavity under the action of the circumferential pressure difference. As a further optimized solution, the injection device also includes an injection main pipe 3, with the injection branch pipes 1 connected to one end of the injection main pipe 3, and the injection branch pipes 1 uniformly distributed circumferentially along the injection main pipe 3. Those skilled in the art can reasonably set the radial angle between the injection branch pipes 1 and the injection main pipe 3, as well as the axial angle between the injection branch pipes 1 and the injection main pipe 3, according to actual conditions.

[0034] The injection pressure is divided into high-pressure injection and low-pressure injection, and the corresponding injection branch pipe 1 is the high-pressure injection branch pipe 1 and the low-pressure injection branch pipe 1. The control device can control the opening degree of the flow regulating device 2 using the following scheme: When the number of high-pressure injection branch pipes 1 is set to one in the initial stage of fluid medium injection, the number of high-pressure injection branch pipes 1 increases with the extension of fluid medium injection time during the fluid medium injection process. That is, along the circumference of the injection port of the cavity to be filled, the opening of the flow regulating device 2 is controlled by the control device in a clockwise or counterclockwise direction, so that the opening of the flow regulating device 2 of the low-pressure injection branch pipe 1 adjacent to the high-pressure injection branch pipe 1 is increased, so that they are sequentially adjusted to high-pressure injection branch pipe 1. Alternatively, during the fluid medium injection process, the number of high-pressure injection openings remains unchanged, but the position of the high-pressure injection openings changes with the extension of fluid medium injection time. That is, along the circumference of the injection port of the cavity to be filled, the opening of the flow regulating device 2 is controlled by the control device in a clockwise or counterclockwise direction, so that the opening of the flow regulating device 2 of the low-pressure injection branch pipe 1 adjacent to the high-pressure injection branch pipe 1 is increased, so that they are sequentially adjusted to high-pressure injection branch pipe 1, while the opening of the original high-pressure injection branch pipe 1's flow regulating device 2 is decreased, adjusting it to low-pressure injection branch pipe 1.

[0035] When the number of high-pressure injection branch pipes 1 is set to multiple in the initial stage of fluid medium injection, and there is at least one low-pressure injection branch pipe 1 between any two adjacent high-pressure injection branch pipes 1, the number of high-pressure injection branch pipes 1 and low-pressure injection branch pipes 1 remains unchanged, and the positions of high-pressure injection branch pipes 1 and low-pressure injection branch pipes 1 are adjusted according to a set time interval to form a circumferential non-equilibrium pressure field that changes with time in the cavity to be filled; during the process of adjusting the opening of the flow regulating device 2, it is always ensured that there is at least one low-pressure injection branch pipe 1 between two adjacent high-pressure injection branch pipes 1; or, when there are no less than two low-pressure injection branch pipes 1 between adjacent high-pressure injection branch pipes 1, the number of high-pressure injection branch pipes 1 and low-pressure injection branch pipes 1 changes, and the opening of the flow regulating device 2 is controlled by the control device to increase the number of high-pressure injection branch pipes 1 by one or more according to a set time interval, and there is at least one low-pressure injection branch pipe 1 between the newly added high-pressure injection branch pipe 1 and the adjacent original high-pressure injection branch pipe 1. At the same time, when the number of newly added high-pressure injection branch pipes 1 is at least two, the condition that there is at least one low-pressure injection branch pipe 1 between adjacent high-pressure injection branch pipes 1 is also met.

[0036] In addition, after the opening of the flow regulating device 2 is fixed before the fluid medium is injected, that is, after the positions of the high-pressure injection branch pipe 1 and the low-pressure injection branch pipe 1 are determined, the opening of the flow regulating device 2 will not be adjusted again during the fluid medium injection, so that the opening of the flow regulating device 2 of the injection branch pipe 1 is always fixed.

[0037] refer to Figure 3 In this embodiment, the cavity to be filled can be selected as the shell 4 of a solid rocket motor. The shell 4 also has an overflow trough to discharge any gas generated or retained during the filling process. The corresponding fluid medium is the propellant (i.e., solid propellant). First, the injection device is installed at the injection port of the shell 4. The opening of the flow regulating device 2 is controlled by the control device to independently control the pressure and flow rate of each injection branch pipe 1. At least one injection branch pipe 1 is in a high-pressure feeding state, with the propellant feeding pressure not lower than 0.3 MPa. Alternatively, the injection branch pipe 1 may be in a low-pressure feeding state, with the propellant feeding pressure not higher than 10 MPa. kPa; then, through the action of the high-pressure feed injection branch pipe 1 and the low-pressure feed injection branch pipe 1, a circumferential pressure difference is formed in the shell 4, and a non-equilibrium pressure field is constructed, thereby driving the propellant to circumferentially sweep from the high-pressure area to the low-pressure area, while the gas flows out from the overflow groove; under the action of the non-equilibrium pressure field and the circumferential sweep flow, the propellant fills the interior of the shell 4 and covers the area where the protruding structure inside the shell 4 is located, until the protruding structure area is filled to a predetermined degree or completely filled by the propellant.

[0038] As a further optimization, the control device is also equipped with a programmable control system, which can adjust the opening of the flow regulating device 2 in real time based on the actual usage. Those skilled in the art will understand that the injection pressure is not limited to the above-mentioned setting range. Relevant practitioners can set the injection pressure reasonably according to the specific structure of the housing 4 and the injection time. At the same time, the flow regulating device 2 is a proportional servo valve, an electro-hydraulic servo valve or an electric servo valve, that is, any device that can continuously adjust the opening is acceptable.

[0039] It should be noted that, for those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A method for injecting a fluid medium, used to inject a fluid medium into a cavity to be filled, characterized in that, The method for injecting the fluid medium includes the following steps: Multiple injection points are arranged circumferentially along the injection port of the cavity to be filled. The fluid medium is injected into the cavity to be filled along the injection points, and the fluid medium pressure at at least one injection point is higher than the fluid medium pressure at the other injection points, so that the fluid medium entering the cavity to be filled forms a circumferential sweeping flow along the cavity under the action of the circumferential pressure difference.

2. The method for injecting a fluid medium according to claim 1, characterized in that, The injection point with the highest fluid medium injection pressure is called the high-pressure injection point, and the other injection points are called low-pressure injection points. The fluid medium injection pressure at the high-pressure injection point is not lower than 0.3 MPa.

3. The method for injecting a fluid medium according to claim 2, characterized in that, The injection pressure of the fluid medium at the low-pressure injection point is not higher than 10 kPa.

4. The method for injecting a fluid medium according to claim 2, characterized in that, It also includes adjusting the fluid medium injection pressure at the injection point to change the positions of the high-pressure injection point and the low-pressure injection point.

5. The method for injecting a fluid medium according to claim 2, characterized in that, The fluid medium injection pressure at the injection point remains constant.

6. The method for injecting a fluid medium according to claim 4, characterized in that, The number of high-pressure injection points is one during the initial stage of fluid medium injection. During the fluid medium injection process, the number of high-pressure injection points increases as the fluid medium injection time increases. The number of high-pressure injection points increases by adjusting the low-pressure injection points adjacent to the high-pressure injection points sequentially as high-pressure injection points along the circumference of the injection port of the cavity to be filled in a clockwise or counterclockwise direction. or, During the injection of the fluid medium, the number of high-pressure injection points remains constant, while the position of the high-pressure injection points changes as the fluid medium injection time increases. The position of the high-pressure injection points changes in the following manner: Along the circumference of the injection port of the cavity to be filled, in a clockwise or counterclockwise direction, the low-pressure injection point adjacent to the high-pressure injection point is sequentially adjusted to become the high-pressure injection point, while the original high-pressure injection point is adjusted to become the low-pressure injection point.

7. The method for injecting a fluid medium according to claim 4, characterized in that, The number of high-pressure injection points is multiple during the initial stage of fluid medium injection, and there is at least one low-pressure injection point between any two adjacent high-pressure injection points; The number of high-pressure injection points and low-pressure injection points remains unchanged, and the positions of the high-pressure injection points and low-pressure injection points are adjusted according to a set time interval, so as to form a circumferential non-equilibrium pressure field that varies with time in the cavity to be filled. or, When there are at least two low-pressure injection points between adjacent high-pressure injection points, the number of high-pressure injection points and the number of low-pressure injection points change, and the number of high-pressure injection points increases by one or more at a set time interval.

8. The method for injecting a fluid medium according to claim 3, characterized in that, The pressure difference between the high-pressure injection point and the low-pressure injection point is not less than 0.1 MPa.

9. A fluid medium injection device for injecting a fluid medium into a cavity to be filled, characterized in that, include: Multiple injection branches are used for circumferential multi-point injection into the cavity to be filled; A flow regulating device is provided on each of the injection branches; A control device communicatively connected to the flow regulating device, the control device being used to control the opening degree of the flow regulating device so that the injection pressure at at least one injection point is different from the injection pressure at the other injection points, so as to control the fluid medium entering the cavity to be filled to form a circumferential sweeping flow along the filling cavity under the action of the circumferential pressure difference.

10. The fluid medium injection device according to claim 9, characterized in that, It also includes an injection manifold, with the injection branch pipes connected to one end of the injection manifold, and the injection branch pipes are evenly distributed circumferentially along the injection manifold.

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