Low-temperature cavitation venturi tube and flow control device for chemical machinery

Abstract

The present invention provides a low-temperature cavitation venturi tube and a flow control device for chemical machinery. The venturi tube includes: a tube body assembly, which forms a fluid channel and a cooling channel; a valve core, at least part of which is arranged in the fluid channel; and a driving mechanism, which is connected to the valve core and drives the valve core to reciprocate axially along the fluid channel, so as to adjust the opening degree of a first gap formed by the valve core and the inner wall of the fluid channel. At least part of the cooling channel is arranged on the outer wall of the fluid channel, and the outlet end of the cooling channel is communicated with the atmospheric environment. Since there are two paths of low-temperature fluid flowing in the tube body assembly, the low-temperature fluid in the fluid channel is transported outward, and the fluid in the cooling channel will pass through the corresponding outer wall of the fluid channel to exchange heat with the tube body assembly, and the low-temperature fluid after heat exchange is discharged into the atmospheric environment until the temperature of the outer wall of the fluid channel is the same as or close to the temperature of the low-temperature fluid in the fluid channel, thereby suppressing the gasification phenomenon of the low-temperature fluid in the fluid channel.

Description

Technical Field

[0001] The present invention relates to the technical field of flow regulation in chemical machinery, and particularly to a cryogenic cavitation venturi tube and a flow control device for chemical machinery. Background Art

[0002] As a key device for controlling the flow rate of cryogenic fluids in chemical machinery, venturi tubes are widely used in the transportation and process regulation of cryogenic media such as liquid nitrogen, liquid oxygen, and liquefied natural gas (LNG). In chemical production, the precise control of the flow rate of cryogenic fluids is directly related to reaction efficiency, energy consumption, and product quality. For example, the injection of liquid nitrogen needs to match the cooling rate of the reaction kettle, and the transportation of liquefied natural gas needs to maintain the dynamic balance of pipeline pressure and flow rate. However, the flow regulation performance of traditional venturi tubes faces significant technical bottlenecks in low-temperature environments: the physical property changes of cryogenic fluids (such as increased viscosity and enhanced phase change sensitivity) will cause a non-linear shift in the relationship between the throat velocity and pressure difference, making the flow-pressure characteristics of venturi tubes with a fixed throat diameter deviate from the design expectations and making it difficult to achieve stable control; moreover, the adjustment method relying on external valve throttling not only has high energy consumption but also causes flow fluctuations due to problems such as valve action lag and seal failure in low-temperature environments. In addition, although existing adjustable venturi tubes can change the throat cross-sectional area through mechanical structures, their adjustment mechanisms are prone to jamming or displacement deviation under the low-temperature contraction effect, and cavitation is more likely to be triggered when cryogenic fluids accelerate in the throat. The generation and collapse of cavitation bubbles will interfere with the flow field stability and further reduce the flow control accuracy.

[0003] At present, there is an urgent need in the field of chemical machinery for a venturi tube structure that can adaptively adjust the throat flow state, suppress cavitation interference, and maintain high-precision flow output within a wide low-temperature range (such as -196°C to -50°C) to meet the stringent requirements of scenarios such as cryogenic medium transportation, reaction cooling, and energy recovery.

[0004] In view of this, the present invention is specifically proposed. Summary of the Invention

[0005] The present invention provides a cryogenic cavitation venturi tube and a flow control device for chemical machinery to solve the technical problem of low flow regulation and control accuracy of existing cryogenic cavitation venturi tubes due to the gasification phenomenon of cryogenic fluids.

[0006] In a first aspect, the present invention provides a low-temperature cavitation venturi tube, comprising: a tube body assembly forming a fluid passage and a cooling passage; a valve core at least partially disposed in the fluid passage; and a driving mechanism connected to the valve core and driving the valve core to reciprocate axially along the fluid passage for adjusting the opening degree of a first gap formed between the valve core and the inner wall of the fluid passage so as to adjust the fluid flow rate in the fluid passage. Wherein, at least part of the cooling passage is disposed on the outer wall of the fluid passage, and the outlet end of the cooling passage is used for communicating with the atmospheric environment.

[0007] In some embodiments, the tube body assembly comprises: a main tube body forming a first connection passage and a second liquid outlet passage; an inlet end tube body installed on the main tube body and forming a first liquid inlet passage; and an outlet end tube body installed on the main tube body and forming a first liquid outlet passage and a second connection passage, the outlet end tube body and the main tube body together form a second liquid inlet passage, and the second connection passage is disposed on the outer wall of at least part of the first liquid outlet passage. Wherein, the first liquid inlet passage, the first connection passage and the first liquid outlet passage are sequentially communicated to form the fluid passage, the second liquid inlet passage, the second connection passage and the second liquid outlet passage are sequentially communicated to form the cooling passage, and the second liquid inlet passage is communicated with the first connection passage.

[0008] In some embodiments, the first liquid outlet passage comprises a converging section flow passage, a throat flow passage and a diverging section flow passage that are sequentially communicated along the axial direction, and the converging section flow passage is located on the side of the throat flow passage close to the first connection passage in the axial direction. The second connection passage is at least disposed on the outer wall of the throat flow passage.

[0009] In some embodiments, the second liquid outlet passage comprises an installation section, an adjustment section and a discharge section that are communicated with each other, and the outlet end of the discharge section is used for communicating with the atmospheric environment. The low-temperature cavitation venturi tube further comprises an adjustment component, the adjustment component is connected to the installation section, and a second gap with an adjustable opening degree is formed between a part of the adjustment component and the inner wall of the adjustment section to adjust the fluid flow rate entering the discharge section.

[0010] In some embodiments, the adjustment component and the main tube body are made of materials with different expansion rates, and the expansion degree of the main tube body under the temperature difference effect with the fluid is greater than the expansion degree of the adjustment component under the temperature difference effect with the fluid to adjust the opening degree of the second gap formed between the adjustment component and the inner wall of the adjustment section.

[0011] In some embodiments, the adjusting member includes an adjusting screw, the adjusting screw includes a connecting section and a mating section, the connecting section is threadedly connected to the inner wall of the mounting section, and at least a part of the mating section is formed as a conical structure. The connecting section is configured to be able to move relative to the mounting section under an external force, so that different parts of the mating section can form the second gap with the inner wall of the adjusting section.

[0012] In some embodiments, the adjusting member further includes a servo electric cylinder, the servo electric cylinder is connected to the connecting section, and is configured to drive the connecting section to move, so as to adjust the depth of the connecting section screwed into the mounting section.

[0013] In some embodiments, the adjusting member further includes a measuring unit and a control unit, the measuring unit is configured to monitor the temperature of the part of the main body forming the adjusting section. The control unit is connected to the measuring unit and the servo electric cylinder, and is configured to control the servo electric cylinder according to the temperature monitored by the measuring unit, so as to adjust the opening degree of the second gap formed by the mating section and the inner wall of the adjusting section.

[0014] In some embodiments, the valve core includes a main body portion and an adjusting portion, the main body portion is connected to the driving mechanism, at least a part of the adjusting portion is formed as a conical structure, and the main body portion can drive the adjusting portion to reciprocate axially relative to the first liquid outlet channel under the action of the driving mechanism, so as to adjust the fluid flow rate in the first liquid outlet channel.

[0015] In some embodiments, heat exchange fins are formed on the part of the main body close to the driving mechanism.

[0016] In some embodiments, the driving mechanism includes a driving motor, a ball screw, a coupling and an adapter, one end of the ball screw is connected to the driving motor through the coupling, and the other end is connected to the valve core through the adapter, and the ball screw is configured to convert the rotational motion of the driving motor into the linear motion of the adapter, so as to drive the valve core to reciprocate axially.

[0017] In some embodiments, the driving motor includes a motor tube body and a motor shaft extending out of the motor tube body. The driving mechanism further includes: a mounting frame, located axially between the motor tube body and the tube body assembly; a limit connecting member, connected to the adapter and the valve core; a limit bearing, disposed on the limit connecting member; and a limit optical axis, disposed on the mounting frame and opposite to the limit bearing, and the limit optical axis is configured to abut against the limit bearing to limit the axial movement of the limit bearing.

[0018] In a second aspect, the present invention provides a flow control device for chemical machinery, which includes the cryogenic cavitation venturi tube described above.

[0019] Compared with the prior art, the cryogenic cavitation venturi tube and the flow control device for chemical machinery provided by the present invention have at least the following beneficial effects:

[0020] In the present application, the tube body assembly serves as the housing structure of the cryogenic cavitation venturi tube, which is mainly used to form a flow channel for the low-temperature fluid to flow through. The valve core and the driving mechanism constitute a regulating valve mechanism. The valve core serves as the regulating valve body, and the driving mechanism serves as the power mechanism of the regulating valve. Based on the cooperation between the valve core and the driving mechanism, the opening degree of the first gap formed by the valve core and the inner wall of the fluid channel can be changed, thereby realizing the regulation of the fluid flow rate in the fluid channel by the valve core. Moreover, since the tube body assembly is simultaneously formed with a fluid channel and a cooling channel, at least a part of the cooling channel is arranged on the outer wall of the fluid channel, and the outlet end of the cooling channel is directly communicated with the atmospheric environment. It is equivalent to having two paths of low-temperature fluid flowing in the tube body assembly. The low-temperature fluid in the fluid channel is used for outward transportation, and the low-temperature fluid in the cooling channel will pass through the corresponding outer wall of the fluid channel during the flowing process to exchange heat with the tube body assembly. And the low-temperature fluid in the cooling channel after exchanging heat with the tube body assembly can be discharged into the atmospheric environment in time until the temperature of the outer wall of the fluid channel is the same as or close to the temperature of the low-temperature fluid in the fluid channel. This reduces the temperature difference between the low-temperature fluid in the fluid channel and the outer wall of the fluid channel, thereby being able to suppress the gasification phenomenon of the low-temperature fluid in the fluid channel, and further improving the flow control accuracy of the low-temperature fluid at the outlet of the fluid channel. In addition, based on the cooperation between the fluid channel and the cooling channel, the amount of heat-insulating material can be reduced, making the overall structure of the cryogenic cavitation venturi tube more compact and applicable to a relatively compact system.

[0021] Other features and advantages of the cryogenic cavitation venturi tube and the flow control device for chemical machinery provided by the present invention will be further described in the subsequent specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required to be used in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative efforts.

[0023] Figure 1 It is a three-dimensional view of the cryogenic cavitation venturi tube provided by the embodiment of the present application;

[0024] Figure 2Schematic diagram of the external structure of the cryogenic cavitation venturi tube provided by the embodiment of the present application;

[0025] Figure 3 Schematic diagram of the internal structure of the cryogenic cavitation venturi tube provided by the embodiment of the present application;

[0026] Figure 4 Schematic diagram of the internal flow channel structure of the cryogenic cavitation venturi tube provided by the embodiment of the present application;

[0027] Figure 5 Schematic diagram of the internal flow channel structure of the outlet end pipe body provided by the embodiment of the present application;

[0028] Figure 6 Schematic diagram of a regulating component provided by the embodiment of the present application;

[0029] Figure 7 Schematic diagram of another regulating component provided by the embodiment of the present application.

[0030] The reference numerals are as follows:

[0031] 100, cryogenic cavitation venturi tube;

[0032] 10, pipe body assembly; 11, main pipe body; 111, heat exchange fins; 12, inlet end pipe body; 13, outlet end pipe body; A, fluid channel; A1, first liquid inlet channel; A2, first connection channel; A3, first liquid outlet channel; A31, contraction section flow channel; A32, throat flow channel; A33, expansion section flow channel; B, cooling channel; B1, second liquid inlet channel; B2, second connection channel; B3, second liquid outlet channel; B31, installation section; B32, regulation section; B33, discharge section;

[0033] 20, valve core; 21, main body part; 22, regulating part;

[0034] 30, drive mechanism; 31, drive motor; 311, motor pipe body; 312, motor shaft; 32, ball screw; 33, coupling; 34, installation frame; 35, adapter; 36, limit connecting piece; 37, limit bearing; 38, limit optical axis;

[0035] 40, regulating component; 41, regulating screw; 411, connection section; 412, mating section; 42, servo electric cylinder;

[0036] 50, sealing component;

[0037] C, axial direction. Detailed implementation manners

[0038] In the description of the present invention, it should be understood that when terms such as "center", "inside", "outside", "axial direction", "radial direction", "circumferential direction" are used to indicate the orientation or positional relationship, without special instructions, it is understood as the orientation or positional relationship shown in the drawings. This is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention.

[0039] In addition, features limited by "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Features limited by "first" and "second" may explicitly or implicitly include at least one of the limited features. When the description "a plurality of" appears, the general meaning is at least two, such as two, three, etc., unless otherwise specifically defined.

[0040] In the present invention, unless otherwise clearly specified and limited, terms such as "installation", "connection", "connection", "fixation" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection, it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] In the description of this specification, when terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" appear, it means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0042] The flow control device provided by the embodiment of the present application for chemical machinery is applied to the field of chemical machinery and can transport and control cryogenic fluids such as liquid nitrogen, liquid oxygen, and liquefied natural gas in chemical machinery. Specifically, the flow control device of the present application can be used in chemical machinery devices or equipment such as cryogenic reactors, cryogenic storage tanks, cryogenic heat exchangers, cryogenic separators, cryogenic pumps, ethylene plants, air separation plants, liquefied natural gas plants (LNG plants), and oxygen production plants.

[0043] The flow control device in this application specifically includes a cryogenic cavitation venturi tube 100. The cryogenic cavitation venturi tube 100 is a flow regulation device that combines the principle of venturi flow regulation and the control of cavitation phenomenon. It controls the flow rate and pressure difference of cryogenic fluids and inhibits the gasification phenomenon of cryogenic fluids by adjusting the valve opening, thereby achieving precise control of the flow rate of cryogenic fluids. Therefore, by using the cryogenic cavitation venturi tube 100 in this application to transport and regulate the flow rate of cryogenic fluids (such as liquid nitrogen, liquid oxygen, liquefied natural gas) in chemical machinery, the overall performance of chemical machinery can be significantly improved.

[0044] Figure 1 is a perspective view of the cryogenic cavitation venturi tube provided by an embodiment of this application. Figure 2 The external structure schematic diagram of the cryogenic cavitation venturi tube provided by an embodiment of this application. Figure 3 is the internal structure schematic diagram of the cryogenic cavitation venturi tube provided by an embodiment of this application.

[0045] Please refer to Figures 1 to 3 , the cryogenic cavitation venturi tube 100 provided by an embodiment of this application includes a tube body assembly 10, a valve core 20, and a driving mechanism 30.

[0046] The tube body assembly 10 is formed with a fluid passage A for the flow of cryogenic fluids and a cooling passage B. Among them, the cryogenic fluid can be a reusable fluid such as liquid nitrogen, liquid hydrogen, liquid oxygen, methane, etc. The cryogenic fluid in the fluid passage A is used for external transportation, while the cryogenic fluid in the cooling passage B is used to cool the part of the tube body assembly 10 corresponding to the fluid passage A.

[0047] At least a part of the valve core 20 is disposed in the fluid passage A, and the valve core 20 is connected to the driving mechanism 30 and reciprocates along the axial direction C of the fluid passage A under the action of the driving mechanism 30.

[0048] The driving mechanism 30 is disposed on one side of the tube body assembly 10 and connected to the valve core 20. It is used to provide power for the valve core 20 so that the valve core 20 can reciprocate along the axial direction C of the fluid passage A, thereby realizing the regulation of the fluid flow rate in the fluid passage A by the valve core 20.

[0049] That is to say, the valve core 20 can extend into different depth positions in the fluid passage A under the action of the driving mechanism 30. At different depth positions, the opening of the first gap formed by the valve core 20 and the inner wall of the fluid passage A is different, thereby realizing the regulation of the fluid flow rate in the fluid passage A by the valve core 20.

[0050] Among them, the cooling passage B is located outside the fluid passage A in the radial direction of the fluid passage A, and at least a part of the cooling passage B is disposed on the outer wall of the fluid passage A. The outlet end of the cooling passage B is also used to communicate with the atmospheric environment.

[0051] In the embodiment of the present application, the pipe body assembly 10 serves as the housing structure of the cryogenic cavitation venturi tube 100. It is mainly used to form a flow channel for the circulation of cryogenic fluid. The valve core 20 and the driving mechanism 30 constitute a regulating valve mechanism. The valve core 20 serves as the regulating valve body, and the driving mechanism 30 serves as the regulating valve power mechanism. Based on the cooperation between the valve core 20 and the driving mechanism 30, the opening degree of the first gap formed by the valve core 20 and the inner wall of the fluid channel A can be changed, thereby realizing the regulation of the fluid flow rate in the fluid channel A by the valve core 20.

[0052] Moreover, since the pipe body assembly 10 simultaneously forms a fluid channel A and a cooling channel B, at least a part of the cooling channel B is arranged on the outer wall of the fluid channel A, and the outlet end of the cooling channel B is directly communicated with the atmospheric environment. It is equivalent to having two paths of cryogenic fluid flowing in the pipe body assembly 10. The cryogenic fluid in the fluid channel A is used for outward transportation, while the cryogenic fluid in the cooling channel B will pass through the corresponding outer wall of the fluid channel A during the flow process to exchange heat with the pipe body assembly 10, and the cryogenic fluid in the cooling channel B after exchanging heat with the pipe body assembly 10 can be discharged into the atmospheric environment in time until the temperature of the outer wall of the fluid channel A is the same as or close to the temperature of the cryogenic fluid in the fluid channel A. This reduces the temperature difference between the cryogenic fluid in the fluid channel A and the outer wall of the fluid channel A, thereby suppressing the gasification phenomenon of the cryogenic fluid in the fluid channel A, and further improving the flow control accuracy of the cryogenic fluid at the outlet of the fluid channel A. In addition, based on the cooperation between the fluid channel A and the cooling channel B, the amount of heat-insulating material can be reduced, making the overall structure of the cryogenic cavitation venturi tube 100 more compact, and it can be used in relatively compact systems, such as in aerospace.

[0053] Figure 4 It is a schematic diagram of the internal flow channel structure of the cryogenic cavitation venturi tube provided by the embodiment of the present application, where the arrow direction in the figure is the flow direction of the cryogenic fluid.

[0054] Please refer to Figure 3 and Figure 4 , the pipe body assembly 10 includes a main pipe body 11, an inlet end pipe body 12, and an outlet end pipe body 13.

[0055] The main pipe body 11 serves as the main structure of the pipe body assembly 10, and it forms a first connection channel A2 and a second liquid outlet channel B3.

[0056] The inlet end pipe body 12 is installed on the main pipe body 11 and is hermetically connected to the main pipe body 11. For example, a sealing structure such as a sealing ring can be provided between the inlet end pipe body 12 and the main pipe body 11. The inlet end pipe body 12 forms a first liquid inlet channel A1, and the first liquid inlet channel A1 is communicated with the first connection channel A2. The first liquid inlet channel A1 is used to receive cryogenic fluid and transport the received cryogenic fluid to the first connection channel A2.

[0057] The outlet end pipe body 13 is installed on the main pipe body 11 and is hermetically connected to the main pipe body 11. For example, a sealing structure such as a sealing ring can be provided between the outlet end pipe body 13 and the main pipe body 11. The outlet end pipe body 13 is formed with a first liquid outlet channel A3 and a second connection channel B2. The first liquid outlet channel A3 communicates with the first connection channel A2. The first liquid outlet channel A3 is used for conveying low-temperature fluid outwards. The second connection channel B2 is arranged on the outer wall of at least a part of the first liquid outlet channel A3. Moreover, the outlet end pipe body 13 and the main pipe body 11 together form a second liquid inlet channel B1. The second liquid inlet channel B1 communicates with the second connection channel B2. The second liquid inlet channel B1 is used for receiving low-temperature fluid and conveying the received low-temperature fluid to the second connection channel B2.

[0058] Among them, the first liquid inlet channel A1, the first connection channel A2, and the first liquid outlet channel A3 are sequentially communicated to form a fluid channel A. The second liquid inlet channel B1, the second connection channel B2, and the second liquid outlet channel B3 are sequentially communicated to form a cooling channel B. And the second liquid inlet channel B1 communicates with the first connection channel A2.

[0059] In this embodiment, the main pipe body 11, the inlet end pipe body 12, and the outlet end pipe body 13 integrally constitute the pipe body assembly 10 of the present application. By forming the mutually connected fluid channel A and cooling channel B on the main pipe body 11, the inlet end pipe body 12, and the outlet end pipe body 13, and arranging the second connection channel B2 of the cooling channel B on the outer wall of at least a part of the first liquid outlet channel A3 of the fluid channel A, the low-temperature fluid is divided into two paths after entering the first connection channel A2 from the first liquid inlet channel A1. One path flows out of the cooling channel B through the second liquid inlet channel B1, the second connection channel B2, and the second liquid outlet channel B3 and is discharged into the atmospheric environment. The other path is conveyed to other mechanisms of the chemical machinery through the second liquid outlet channel B3. Thus, the conveyance of the low-temperature fluid in the chemical machinery and the cooling of the outlet end pipe body 13 by the low-temperature fluid are realized, thereby reducing the temperature difference between the outlet end pipe body 13 and the low-temperature fluid therein. Thereby, the gasification phenomenon of the low-temperature fluid in the outlet end pipe body 13 can be inhibited, and further, the flow control accuracy of the low-temperature fluid at the outlet of the outlet end pipe body 13 is improved. Moreover, by forming different parts of the fluid channel A and the cooling channel B on the main pipe body 11, the inlet end pipe body 12, and the outlet end pipe body 13 and making the fluid channel A and the cooling channel B communicate with each other through the corresponding parts, the structures of the fluid channel A and the cooling channel B are compact, the space utilization rate on the pipe body assembly 10 is improved, and the low-temperature cavitation venturi tube 100 of the present application can be used in a relatively compact system.

[0060] Figure 5 It is a schematic diagram of the internal flow channel structure of the outlet end pipe body provided by the embodiment of the present application.

[0061] Please refer to Figure 4and Figure 5 The first liquid outlet channel A3 includes a converging section flow channel A31, a throat flow channel A32, and a diverging section flow channel A33 that are sequentially connected along its axial direction C. The converging section flow channel A31 is located on the side of the throat flow channel A32 close to the first connection channel A2 in the axial direction C. That is to say, the converging section flow channel A31, the throat flow channel A32, and the diverging section flow channel A33 are sequentially connected along the flow direction of the low-temperature fluid. Among them, the second connection channel B2 of the cooling channel B is at least arranged on the outer wall of the throat flow channel A32 of the first liquid outlet channel A3.

[0062] It should be noted that since the converging section flow channel A31, the throat flow channel A32, and the diverging section flow channel A33 of the first liquid outlet channel A3 are sequentially connected along the flow direction of the low-temperature fluid, after the low-temperature fluid enters the first connection channel A2 from the first liquid inlet channel A1, the low-temperature fluid reaching the first liquid outlet channel A3 will first enter the converging section flow channel A31 to accelerate. According to Bernoulli's principle, the increase in fluid velocity will lead to a decrease in its static pressure. When the static pressure drops below the saturated vapor pressure of the low-temperature fluid, cavitation will occur in the pipe. At this time, the fluid flow rate is only affected by the inlet pressure, the diameter of the throat flow channel A32, and the saturated vapor pressure of the low-temperature fluid, and is not affected by the downstream outlet pressure. Therefore, based on this principle, through the cooperation of the valve core 20 and the driving mechanism 30, the flow area of the throat flow channel A32 (i.e., the opening of the first gap formed by the valve core 20 and the inner wall of the throat flow channel A32) can be adjusted, so as to realize the flow control in the first liquid outlet channel A3, thereby ensuring more sufficient cavitation of the low-temperature fluid in the first liquid outlet channel A3 and improving the stability of the flow rate. Finally, the low-temperature fluid decelerates through the diverging section flow channel A33 after passing through the throat flow channel A32 to increase the static pressure of the low-temperature fluid, so that the fluid that evaporates after the static pressure of the low-temperature fluid is greater than its saturated vapor pressure is condensed again and flows out from the outlet of the diverging section flow channel A33.

[0063] In this embodiment, since the second connection channel B2 of the cooling channel B is at least arranged on the outer wall of the throat flow channel A32 of the first liquid outlet channel A3, when the low-temperature fluid in the cooling channel B flows through the second connection channel B2, the low-temperature fluid can exchange heat with the outer wall of the throat flow channel A32, thereby greatly reducing the temperature of the part of the pipe body assembly 10 that forms the throat flow channel A32. It reduces the temperature difference between the low-temperature fluid in the throat flow channel A32 and the part of the pipe body assembly 10 that forms the throat flow channel A32, thereby being able to suppress the gasification phenomenon of the low-temperature fluid in the throat flow channel A32, and further improving the cavitation effect of the low-temperature fluid at the throat flow channel A32, thereby improving the flow control accuracy of the low-temperature fluid at the outlet of the first liquid outlet channel A3.

[0064] Please refer to Figure 3 、 Figure 4 and Figure 5, the valve core 20 includes a main body portion 21 and an adjustment portion 22. One end of the main body portion 21 is connected to the driving mechanism 30, and the other end is connected to the adjustment portion 22. At least a part of the adjustment portion 22 is formed into a conical structure. For example, the adjustment portion 22 is integrally formed into a conical structure or the end of the adjustment portion 22 far from the main body portion 21 is formed into a conical structure. The present application does not make specific limitations. Among them, the main body portion 21 can drive the adjustment portion 22 to reciprocate axially C relative to the throat flow channel A32 of the first liquid outlet channel A3 under the action of the driving mechanism 30 to adjust the fluid flow rate in the throat flow channel A32 of the first liquid outlet channel A3.

[0065] Based on the fact that at least a part of the adjustment portion 22 is formed into a conical structure, under the action of the driving mechanism 30, different parts of the adjustment portion 22 can enclose a first gap with different opening degrees with the throat flow channel A32 of the first liquid outlet channel A3, thereby realizing the control of the flow area of the throat flow channel A32. Moreover, in the present application, by controlling the movement of the valve core 20 by the driving mechanism 30, the adjustment of the size of the flow area of the throat flow channel A32 can be realized. Its structure is simple, with high precision and good practicability.

[0066] Please refer to Figure 3 and Figure 4 , the second liquid outlet channel B3 includes an installation section B31, an adjustment section B32 and a discharge section B33 that are connected to each other. The outlet end of the discharge section B33 is used to communicate with the atmospheric environment. Among them, the cryogenic cavitation venturi tube 100 further includes an adjustment component 40. The adjustment component 40 is connected to the installation section B31, and a part of the adjustment component 40 and the inner wall of the adjustment section B32 enclose an adjustable second gap to adjust the fluid flow rate entering the discharge section B33.

[0067] Since a part of the adjustment component 40 can enclose an adjustable second gap with the inner wall of the adjustment section B32, the fluid flow rate entering the discharge section B33 can be adjusted based on the change in the opening degree of the second gap, thereby ensuring the stable flow rate of the cryogenic fluid at the outlet of the first liquid outlet channel A3.

[0068] In some embodiments, the adjustment component 40 and the main pipe body 11 are made of materials with different expansion rates, and the expansion degree of the main pipe body 11 under the temperature difference effect with the cryogenic fluid is greater than the expansion degree of the adjustment component 40 under the temperature difference effect with the cryogenic fluid (correspondingly, the contraction degree of the main pipe body 11 under the temperature difference effect with the cryogenic fluid is greater than the contraction degree of the adjustment component 40 under the temperature difference effect with the cryogenic fluid) to adjust the opening degree of the second gap enclosed by the adjustment component 40 and the inner wall of the adjustment section B32.

[0069] Understandably, in order to ensure that the expansion degree of the main pipe body 11 under the temperature difference with the low-temperature fluid is greater than that of the adjusting component 40 under the temperature difference with the low-temperature fluid, the adjusting component 40 can be made of a material with a low expansion rate (such as a metal material), and the main pipe body 11 is made of a material with a high expansion rate (such as a metal material).

[0070] Based on the fact that the adjusting component 40 and the main pipe body 11 are made of materials with different expansion rates, at the initial stage of low-temperature fluid transportation, the temperature difference between the main pipe body 11 and the low-temperature fluid inside it is the largest. Since the expansion degree of the main pipe body 11 under the temperature difference with the low-temperature fluid is greater than that of the adjusting component 40 under the temperature difference with the low-temperature fluid, the opening degree of the second gap formed by the adjusting component 40 and the inner wall of the adjusting section B32 is the largest, so that the fluid flow rate entering the discharge section B33 is the largest; as the temperature difference between the main pipe body 11 and the low-temperature fluid inside it gradually decreases, the main pipe body 11 and the adjusting component 40 begin to gradually contract, and the opening degree of the second gap formed by the adjusting component 40 and the inner wall of the adjusting section B32 gradually decreases, so that the fluid flow rate entering the discharge section B33 gradually decreases; when the temperatures of the main pipe body 11 and the adjusting component 40 are close to the low-temperature fluid (the temperature difference is the smallest), the contraction degree of the main pipe body 11 and the adjusting component 40 is the largest, making the opening degree of the second gap the smallest (close to closing), so that the fluid flow rate entering the discharge section B33 is the smallest.

[0071] Therefore, since the adjusting component 40 and the main pipe body 11 are made of materials with different expansion rates, the opening degree of the second gap formed by the adjusting component 40 and the inner wall of the adjusting section B32 can adaptively increase with the increase of the temperature difference and decrease with the decrease of the temperature difference. Thus, without manual or electric cylinder adjustment, the fluid flow rate into the discharge section B33 can be adjusted, ensuring the stable flow rate of the low-temperature fluid at the outlet of the first liquid outlet channel A3. Its structure is simple and the reliability is high.

[0072] Figure 6 It is a schematic structural diagram of an adjusting component provided by an embodiment of the present application, and also Figure 3 an enlarged view of the circled part in

[0073] In some embodiments, please refer to Figure 3 and Figure 6 , the adjusting component 40 includes an adjusting screw 41. The adjusting screw 41 includes a connecting section 411 and a matching section 412. The connecting section 411 is threadedly connected to the inner wall of the installation section B31, and at least part of the matching section 412 is formed as a conical structure. Among them, the connecting section 411 is arranged to be able to move relative to the installation section B31 under an external force, so that different parts of the matching section 412 can form second gaps with different opening degrees with the inner wall of the adjusting section B32.

[0074] In this embodiment, based on the threaded connection between the connection section 411 of the adjusting screw 41 and the inner wall of the installation section B31, the depth of the connection section 411 of the adjusting screw 41 screwed into the installation section B31 can be manually adjusted by using a tool. After the throat flow channel A32 is cooled in place by the low-temperature fluid in the cooling channel B, the adjusting screw 41 can be screwed clockwise, so that the opening degree of the second gap formed by the mating section 412 and the inner wall of the adjusting section B32 is reduced, and the flow rate is smaller; when the temperature difference is large, the adjusting screw 41 is screwed counterclockwise, so that the opening degree of the second gap formed by the mating section 412 and the inner wall of the adjusting section B32 is increased, and the flow rate is increased. Therefore, by controlling the adjusting screw 41 to be screwed into or out of the installation section B31, different parts of the mating section 412 can form second gaps with different opening degrees with the inner wall of the adjusting section B32, thereby controlling the fluid flow rate into the discharge section B33, and further improving the cooling efficiency of the low-temperature fluid in the cooling channel B on the outlet end pipe body 13.

[0075] Figure 7 It is a schematic structural diagram of another adjusting component provided by the embodiment of the present application.

[0076] In some embodiments, please refer to Figure 7 , the adjusting component 40 includes an adjusting screw 41 and a servo electric cylinder 42. The adjusting screw 41 includes a connection section 411 and a mating section 412. The connection section 411 is threadedly connected to the inner wall of the installation section B31, and at least part of the mating section 412 is formed into a conical structure. The servo electric cylinder 42 is connected to the connection section 411 and is used to drive the connection section 411 to move, so as to adjust the depth of the connection section 411 screwed into the installation section B31, so that different parts of the mating section 412 can form second gaps with different opening degrees with the inner wall of the adjusting section B32.

[0077] By driving the connection section 411 to move through the servo electric cylinder 42 to adjust the depth of the connection section 411 screwed into the installation section B31, the cooling efficiency of the low-temperature fluid in the cooling channel B on the outlet end pipe body 13 can be further improved.

[0078] Furthermore, the adjusting component 40 further includes a measuring unit and a control unit. The measuring unit is used to monitor the temperature of the part of the main pipe body 11 that forms the adjusting section B32. The control unit is connected to the measuring unit and the servo electric cylinder 42, and is used to control the servo electric cylinder 42 according to the temperature monitored by the measuring unit, so as to adjust the opening degree of the second gap formed by the mating section 412 and the inner wall of the adjusting section B32.

[0079] Specifically, based on the pre-set data relationship between the temperature of the main pipe body 11 and the opening degree of the second gap, when the temperature difference between the main pipe body 11 and the low-temperature fluid is too large, the servo cylinder 42 is feedback-regulated to increase the opening degree of the second gap; when the temperature difference is small, the servo cylinder 42 is adjusted to reduce the opening degree of the second gap. Therefore, based on the temperature data of the part of the main pipe body 11 that forms the adjustment section B32, the servo cylinder 42 can be closed-loop controlled and adjusted, so as to realize the fully automatic adjustment of the opening degree of the second gap, thereby further improving the cooling efficiency of the low-temperature fluid in the cooling channel B on the outlet end pipe body 13. Moreover, based on the improvement of the cooling efficiency of the low-temperature fluid in the cooling channel B on the outlet end pipe body 13, the emission of the low-temperature fluid from the cooling channel B to the atmospheric environment can be reduced.

[0080] In some embodiments, referring to Figures 1 to 3 , a plurality of heat exchange fins 111 are formed on the part of the main pipe body 11 close to the driving mechanism 30.

[0081] In this embodiment, by providing a plurality of heat exchange fins 111 on the main pipe body 11, during the operation of the low-temperature cavitation venturi tube 100, the air in the atmospheric environment can exchange heat with the plurality of heat exchange fins 111, so as to increase the temperature of one end of the main pipe body 11 close to the driving mechanism 30 by increasing the heat exchange surface area of the main pipe body 11, thereby avoiding the influence of the too low temperature of the main pipe body 11 on the driving mechanism 30.

[0082] In some embodiments, referring to Figures 1 to 3 , the driving mechanism 30 includes a driving motor 31, a ball screw 32, a coupling 33 and an adapter 35. One end of the ball screw 32 is connected to the driving motor 31 through the coupling 33, and the other end is connected to the valve core 20 through the adapter 35. The ball screw 32 is used to convert the rotational motion of the driving mechanism 30 into the linear motion of the adapter 35 to drive the valve core 20 to reciprocate along the axis C.

[0083] In some embodiments, please continue to refer to Figures 1 to 3 , the driving motor 31 includes a motor tube body 311 and a motor shaft 312 extending out of the motor tube body 311. The driving mechanism 30 further includes a mounting frame 34, an adapter 35, a limit connecting member 36, a limit bearing 37 and a limit optical axis 38.

[0084] The mounting frame 34 is located between the motor tube body 311 and the tube assembly 10 in the axis C direction. The limit connecting member 36 is connected to the adapter 35 and the valve core 20. The limit bearing 37 is arranged on the limit connecting member 36. The limit optical axis 38 is arranged on the mounting frame 34 and is arranged opposite to the limit bearing 37, and the limit optical axis 38 is used to abut against the limit bearing 37 to limit the movement of the limit bearing 37 in the axis C direction.

[0085] Specifically, the limit connecting member 36 can be connected to the limit bearing 37 by screws. The limit connecting member 36 can also be connected to the adapter 35 and the valve core 20 by screws, and cooperate with the limit optical axis 38 through the limit bearing 37 to restrict the reciprocating movement of the limit connecting member 36 along the axial direction C.

[0086] In some embodiments, referring to Figure 3 , the low-temperature cavitation venturi tube 100 of the present application further includes a sealing member 50. The sealing member 50 is arranged between the adjusting portion 22 of the valve core 20 and the main pipe body 11 for sealingly connecting the valve core 20 and the main pipe body 11.

[0087] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A low-temperature cavitation venturi tube (100), characterized in that, Comprising: A tube body assembly (10) formed with a fluid passage (A) and a cooling passage (B); A valve core (20) at least partially disposed in the fluid passage (A); And A driving mechanism (30) connected to the valve core (20) and driving the valve core (20) to reciprocate along the axial direction (C) of the fluid passage (A) to adjust the opening degree of a first gap formed between the valve core (20) and the inner wall of the fluid passage (A), so as to adjust the fluid flow rate in the fluid passage (A); Wherein, at least a part of the cooling passage (B) is disposed on the outer wall of the fluid passage (A), and the outlet end of the cooling passage (B) is used for communicating with the atmospheric environment; The tube body assembly (10) includes: A main tube body (11) formed with a first connection passage (A2) and a second liquid outlet passage (B3); An inlet end tube body (12) installed on the main tube body (11) and formed with a first liquid inlet passage (A1); and An outlet end tube body (13) installed on the main tube body (11) and formed with a first liquid outlet passage (A3) and a second connection passage (B2), the outlet end tube body (13) and the main tube body (11) together form a second liquid inlet passage (B1), and the second connection passage (B2) is disposed on at least a part of the outer wall of the first liquid outlet passage (A3); Wherein, the first liquid inlet passage (A1), the first connection passage (A2) and the first liquid outlet passage (A3) are sequentially communicated to form the fluid passage (A), the second liquid inlet passage (B1), the second connection passage (B2) and the second liquid outlet passage (B3) are sequentially communicated to form the cooling passage (B), and the second liquid inlet passage (B1) is communicated with the first connection passage (A2).

2. The cryogenic cavitation venturi tube (100) according to claim 1, characterized in that The first liquid outlet passage (A3) includes a converging section flow passage (A31), a throat flow passage (A32) and a diverging section flow passage (A33) sequentially communicated along the axial direction (C), and the converging section flow passage (A31) is located on the side of the throat flow passage (A32) close to the first connection passage (A2) in the axial direction (C); The second connection passage (B2) is at least disposed on the outer wall of the throat flow passage (A32).

3. The cryogenic cavitation venturi tube (100) according to claim 1, characterized in that The second liquid outlet passage (B3) includes an installation section (B31), an adjustment section (B32) and a discharge section (B33) that are communicated with each other, and the outlet end of the discharge section (B33) is used for communicating with the atmospheric environment; The cryogenic cavitation venturi tube further includes an adjustment component (40), the adjustment component (40) is connected to the installation section (B31), and a part of the adjustment component (40) and the inner wall of the adjustment section (B32) enclose a second gap with an adjustable opening degree to adjust the fluid flow rate entering the discharge section (B33).

4. The low-temperature cavitation venturi tube (100) according to claim 3, characterized in that, The adjusting member (40) is made of a material with a different expansion rate from that of the main body (11), and the expansion degree of the main body (11) under the temperature difference with the fluid is greater than that of the adjusting member (40) under the temperature difference with the fluid, so as to adjust the opening degree of the second gap formed by the adjusting member (40) and the inner wall of the adjusting section (B32).

5. The cryogenic cavitation venturi tube (100) according to claim 3, wherein the adjusting member (40) includes an adjusting screw (41), the adjusting screw (41) includes a connecting section (411) and a mating section (412), the connecting section (411) is threadedly connected to the inner wall of the installation section (B31), and at least part of the mating section (412) is formed as a conical structure; the connecting section (411) is arranged to be able to move relative to the installation section (B31) under an external force, so that different parts of the mating section (412) can form the second gap with the inner wall of the adjusting section (B32).

6. The cryogenic cavitation venturi tube (100) according to claim 5, characterized in that, The adjusting member (40) further includes a servo electric cylinder (42), the servo electric cylinder (42) is connected to the connecting section (411), and is used to drive the connecting section (411) to move, so as to adjust the depth of the connecting section (411) screwed into the installation section (B31).

7. The cryogenic cavitation venturi tube (100) according to claim 6, wherein the adjusting member (40) further includes a measuring unit and a control unit, the measuring unit is used to monitor the temperature of the part of the main body (11) forming the adjusting section (B32); the control unit is connected to the measuring unit and the servo electric cylinder (42), and is used to control the servo electric cylinder (42) according to the temperature monitored by the measuring unit, so as to adjust the opening degree of the second gap formed by the mating section (412) and the inner wall of the adjusting section (B32).

8. The cryogenic cavitation venturi tube (100) according to any one of claims 1-7, wherein the valve core (20) includes a main body part (21) and an adjusting part (22), the main body part (21) is connected to the driving mechanism (30), at least part of the adjusting part (22) is formed as a conical structure, and the main body part (21) can drive the adjusting part (22) to reciprocate axially (C) relative to the first liquid outlet channel (A3) under the action of the driving mechanism (30), so as to adjust the fluid flow rate in the first liquid outlet channel (A3); and / or a heat exchange fin structure (111) is formed on the part of the main body (11) close to the driving mechanism (30); and / or The driving mechanism (30) includes a driving motor (31), a ball screw (32), a coupling (33) and an adapter (35). One end of the ball screw (32) is connected to the driving motor (31) through the coupling (33), and the other end is connected to the valve core (20) through the adapter (35). The ball screw (32) is configured to convert the rotational motion of the driving motor (31) into the linear motion of the adapter (35) to drive the valve core (20) to reciprocate along the axial direction (C).

9. The cryogenic cavitation venturi tube (100) according to claim 8, wherein the driving motor (31) includes a motor housing (311) and a motor shaft (312) extending out of the motor housing (311); the driving mechanism (30) further includes: a mounting frame (34) located between the motor housing (311) and the tube assembly (10) in the axial direction (C); a limit connecting member (36) connected to the adapter (35) and the valve core (20); a limit bearing (37) disposed on the limit connecting member (36); and a limit optical axis (38) disposed on the mounting frame (34) and opposite to the limit bearing (37), and the limit optical axis (38) is configured to abut against the limit bearing (37) to limit the movement of the limit bearing (37) in the axial direction (C).

10. A flow control device for chemical machinery, characterized in that, including the cryogenic cavitation venturi tube (100) according to any one of claims 1-9.

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