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

Abstract

The invention provides a low-temperature cavitation venturi tube and a flow control device for chemical machinery, and the venturi tube comprises a tube body assembly which is provided with a fluid channel and a cooling channel; at least part of the valve element is arranged in the fluid channel; the driving mechanism is connected with the valve element and drives the valve element to do reciprocating motion in the axial direction of the fluid channel so as to be used for adjusting the opening degree of a first gap defined by the valve element 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 communicates with the atmospheric environment. Due to the fact that two paths of circulating low-temperature fluid exist in the pipe body assembly, the low-temperature fluid in the fluid channel is conveyed outwards, the fluid in the cooling channel can pass through the corresponding outer wall of the fluid channel to exchange heat with the pipe body assembly, and the low-temperature fluid obtained after heat exchange is discharged into the atmospheric environment. And the temperature of the outer wall of the fluid channel is consistent with or approximately consistent with the temperature of the low-temperature fluid in the fluid channel, so that the gasification phenomenon of the low-temperature fluid in the fluid channel is inhibited.

Description

Technical Field

[0001] The invention relates to the technical field of flow regulation in chemical machinery, and in particular to a low-temperature cavitation venturi and a flow control device for chemical machinery. Background Art

[0002] As a key device for low-temperature fluid flow control in chemical machinery, the Venturi tube is widely used in the transportation and process control of cryogenic media such as liquid nitrogen, liquid oxygen, and liquefied natural gas (LNG). In chemical production, the precise flow control of cryogenic fluids is directly related to reaction efficiency, energy consumption, and product quality. For example, liquid nitrogen injection needs to match the cooling rate of the reactor, and liquefied natural gas transportation needs to maintain a dynamic balance between pipeline pressure and flow. However, the flow regulation performance of traditional Venturi tubes in low-temperature environments faces significant technical bottlenecks: changes in the physical properties of cryogenic fluids (such as increased viscosity and enhanced sensitivity to phase changes) will lead to nonlinear shifts in the relationship between throat flow velocity and pressure difference, making the flow-pressure difference characteristics of fixed throat diameter Venturi tubes deviate from design expectations and difficult to achieve stable control; and the regulation method that relies on external valve throttling is not only energy-intensive, but also causes flow fluctuations due to problems such as valve hysteresis and seal failure in low-temperature environments. In addition, although the existing adjustable Venturi tube can change the throat cross-sectional area through mechanical structure, its adjustment mechanism is prone to jamming or displacement deviation under the low-temperature contraction effect, and the low-temperature fluid is more likely to trigger cavitation when accelerating 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, the chemical machinery field is in urgent need of a Venturi 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 low-temperature medium transportation, reaction cooling and energy recovery.

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

[0005] The present invention provides a low-temperature cavitation venturi and a flow control device for chemical machinery, so as to solve the technical problem of low flow regulation control accuracy of the existing low-temperature cavitation venturi due to the gasification phenomenon of low-temperature fluid.

[0006] In a first aspect, the present invention provides a low-temperature cavitation venturi, comprising: a tube assembly, formed with a fluid channel and a cooling channel; a valve core, at least partially disposed in the fluid channel; and a driving mechanism, connected to the valve core and driving the valve core to reciprocate along the axial direction of the fluid channel, so as to adjust the opening of a first gap formed by the valve core and the inner wall of the fluid channel, so as to adjust the fluid flow in the fluid channel. Wherein, at least a portion of the cooling channel is disposed on the outer wall of the fluid channel, and the outlet end of the cooling channel is used to communicate with the atmospheric environment.

[0007] In some embodiments, the tube assembly includes: a main tube, formed with a first connecting channel and a second liquid outlet channel; an inlet end tube, mounted on the main tube and formed with a first liquid inlet channel; and an outlet end tube, mounted on the main tube and formed with a first liquid outlet channel and a second connecting channel, the outlet end tube and the main tube together forming a second liquid inlet channel, the second connecting channel being arranged on at least part of the outer wall of the first liquid outlet channel. The first liquid inlet channel, the first connecting channel and the first liquid outlet channel are sequentially connected to form the fluid channel, the second liquid inlet channel, the second connecting channel and the second liquid outlet channel are sequentially connected to form the cooling channel, and the second liquid inlet channel is connected to the first connecting channel.

[0008] In some embodiments, the first liquid outlet channel includes a contraction section flow channel, a throat flow channel and an expansion section flow channel that are sequentially connected along the axial direction, the contraction section flow channel is located on the side of the throat flow channel close to the first connecting channel in the axial direction. The second connecting channel is at least provided on the outer wall of the throat flow channel.

[0009] In some embodiments, the second liquid outlet channel includes a mounting section, an adjusting section and a discharge section that are interconnected, and the outlet end of the discharge section is used to communicate with the atmospheric environment. The low-temperature cavitation venturi also includes an adjusting component, the adjusting component is connected to the mounting section, and a portion of the adjusting component and the inner wall of the adjusting section form a second gap with an adjustable opening to adjust the fluid flow entering the discharge section.

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

[0011] In some embodiments, the adjustment component includes an adjustment screw, the adjustment screw includes a connecting section and a matching section, the connecting section is threadedly connected to the inner wall of the mounting section, and at least a portion of the matching section is formed into a conical structure. The connecting section is configured to be able to move relative to the mounting section under the action of an external force, so that different portions of the matching section can enclose the second gap with the inner wall of the adjustment section.

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

[0013] In some embodiments, the adjustment component further includes a measuring unit and a control unit, wherein the measuring unit is used to monitor the temperature of the portion of the main body forming the adjustment section. The control unit is connected to the measuring unit and the servo electric cylinder, and is used to control the servo electric cylinder according to the temperature monitored by the measuring unit to adjust the opening of the second gap formed by the matching section and the inner wall of the adjustment section.

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

[0015] In some embodiments, a portion of the main pipe close to the driving mechanism is formed with heat exchange fins.

[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 used to convert the rotational motion of the driving motor into the linear motion of the adapter to drive the valve core to reciprocate along the axial direction.

[0017] In some embodiments, the driving motor includes a motor tube body and a motor shaft extending from the motor tube body. The driving mechanism also includes: a mounting frame, located between the motor tube body and the tube body assembly in the axial direction; a limit connector, connected to the adapter and the valve core; a limit bearing, disposed on the limit connector; and a limit optical axis, disposed on the mounting frame and opposite to the limit bearing, and the limit optical axis is used to abut against the limit bearing to limit the movement of the limit bearing in the axial direction.

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

[0019] Compared with the prior art, the low-temperature cavitation venturi and the flow control device for chemical machinery provided by the present invention have at least the following beneficial effects: In the present application, the tube body assembly serves as the shell structure of the low-temperature cavitation venturi, which is mainly used to form a flow channel for the circulation of low-temperature fluid, while 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 regulating valve power mechanism. Based on the cooperation between the valve core and the driving mechanism, the opening of the first gap formed by the valve core and the inner wall of the fluid channel can be changed, thereby realizing the valve core's regulation of the fluid flow in the fluid channel. Moreover, since the tube body assembly is formed with a fluid channel and a cooling channel at the same time, 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 directly connected to the atmosphere, it is equivalent to having two-way low-temperature fluid 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 circulation process to exchange heat with the tube body assembly, and the low-temperature fluid in the cooling channel after heat exchange with the tube body assembly can be discharged to the atmosphere in time until the temperature of the outer wall of the fluid channel is consistent or nearly consistent with the temperature of the low-temperature fluid in the fluid channel, which reduces the temperature difference between the low-temperature fluid in the fluid channel and the outer wall of the fluid channel, thereby suppressing the gasification phenomenon of the low-temperature fluid in the fluid channel, and then improving the flow control accuracy of the low-temperature fluid at the outlet of the fluid channel. In addition, based on the cooperation of the fluid channel and the cooling channel, the amount of insulation material can be reduced, making the overall structure of the low-temperature cavitation venturi more compact, and can be used in a more compact system.

[0020] Other features and advantages of the low-temperature cavitation venturi and the flow control device for chemical machinery provided by the present invention will be further described in the subsequent specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the specific implementation of the present invention or the technical solution in the prior art, the following briefly introduces the drawings required for use in the specific implementation or the prior art description. Obviously, the drawings described below are some implementations of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 A three-dimensional diagram of a low-temperature cavitation venturi provided in an embodiment of the present application; Figure 2 A schematic diagram of the external structure of a low-temperature cavitation venturi provided in an embodiment of the present application; Figure 3 A schematic diagram of the internal structure of a low-temperature cavitation venturi provided in an embodiment of the present application; Figure 4 A schematic diagram of the internal flow channel structure of a low-temperature cavitation venturi provided in an embodiment of the present application; Figure 5 A schematic diagram of the internal flow channel structure of the outlet pipe body provided in an embodiment of the present application; Figure 6 A schematic diagram of the structure of an adjustment component provided in an embodiment of the present application; Figure 7 A schematic diagram of the structure of another adjusting component provided in an embodiment of the present application.

[0023] The reference numerals are as follows: 100. Low temperature cavitation venturi; 10. Tube assembly; 11. Main tube; 111. Heat exchange fins; 12. Inlet tube; 13. Outlet tube; A. Fluid channel; A1. First liquid inlet channel; A2. First connecting 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 connecting channel; B3. Second liquid outlet channel; B31. Installation section; B32. Adjustment section; B33. Discharge section; 20. valve core; 21. main body; 22. regulating part; 30. Driving mechanism; 31. Driving motor; 311. Motor tube; 312. Motor shaft; 32. Ball screw; 33. Coupling; 34. Mounting frame; 35. Adapter; 36. Limiting connector; 37. Limiting bearing; 38. Limiting optical axis; 40. Adjusting component; 41. Adjusting screw; 411. Connecting section; 412. Matching section; 42. Servo electric cylinder; 50. Sealing parts; C. Axial. DETAILED DESCRIPTION

[0024] In the description of the present invention, it is necessary to understand that if terms such as "center", "inside", "outside", "axial", "radial", and "circumferential" appear in the description indicating the orientation or position relationship, unless otherwise specified, it is understood that the orientation or position relationship is based on the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0025] In addition, if there is a feature defined as "first" or "second", it is only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Features defined as "first" or "second" may explicitly or implicitly include at least one of the defined features. If there is a description of "plurality", the general meaning is to include at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0026] In the present invention, unless otherwise clearly specified and limited, the terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection, it can be a direct connection, or it can be an indirect connection through an intermediate medium, it can be the internal connection of 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 the specific circumstances.

[0027] In the description of this specification, if the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" appear, it means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0028] The flow control device for chemical machinery provided in the embodiment of the present application 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 devices, air separation devices, liquefied natural gas devices (LNG devices), and oxygen production devices.

[0029] The flow control device in the present application specifically includes a cryogenic cavitation venturi 100. The cryogenic cavitation venturi 100 is a flow control device that combines the venturi flow control principle and cavitation phenomenon control. It controls the flow rate and pressure difference of the cryogenic fluid and suppresses the gasification phenomenon of the cryogenic fluid by adjusting the valve opening, thereby achieving precise control of the flow of the cryogenic fluid. Therefore, by using the cryogenic cavitation venturi 100 in the present application to transport and regulate the flow of cryogenic fluids (such as liquid nitrogen, liquid oxygen, and liquefied natural gas) in chemical machinery, the overall performance of the chemical machinery can be significantly improved.

[0030] Figure 1 A three-dimensional diagram of a low-temperature cavitation venturi provided in an embodiment of the present application, Figure 2 The external structure diagram of the low-temperature cavitation venturi provided in the embodiment of the present application is as follows: Figure 3 A schematic diagram of the internal structure of a low-temperature cavitation venturi provided in an embodiment of the present application.

[0031] See also Figures 1 to 3 The low-temperature cavitation venturi 100 provided in the embodiment of the present application includes a tube body assembly 10 , a valve core 20 and a driving mechanism 30 .

[0032] The pipe body assembly 10 is formed with a fluid channel A and a cooling channel B for the circulation of a cryogenic fluid. The cryogenic fluid may be a reusable fluid such as liquid nitrogen, liquid hydrogen, liquid oxygen, methane, etc. The cryogenic fluid in the fluid channel A is used for external transportation, while the cryogenic fluid in the cooling channel B is used to cool the portion of the pipe body assembly 10 corresponding to the fluid channel A.

[0033] At least a portion of the valve core 20 is disposed in the fluid channel A, and the valve core 20 is connected to the driving mechanism 30 and reciprocates along the axial direction C of the fluid channel A under the action of the driving mechanism 30 .

[0034] The driving mechanism 30 is arranged on one side of the pipe 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 channel A, thereby realizing the valve core 20 regulating the fluid flow in the fluid channel A.

[0035] That is to say, under the action of the driving mechanism 30, the valve core 20 can extend into different depths in the fluid channel A, and at different depths, the opening of the first gap formed by the valve core 20 and the inner wall of the fluid channel A is different, thereby enabling the valve core 20 to regulate the fluid flow in the fluid channel A.

[0036] The cooling channel B is located outside the fluid channel A in the radial direction of the fluid channel A, and at least a portion of the cooling channel B is arranged on the outer wall of the fluid channel A. The outlet end of the cooling channel B is also used to communicate with the atmospheric environment.

[0037] In the embodiment of the present application, the tube body assembly 10 serves as the shell structure of the low-temperature cavitation venturi 100, which is mainly used to form a flow channel for the circulation of low-temperature fluid, and 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 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 valve core 20 to regulate the fluid flow in the fluid channel A.

[0038] Furthermore, since the tube assembly 10 is formed with a fluid channel A and a cooling channel B at the same time, at least 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 connected to the atmosphere, it is equivalent to having two-way low-temperature fluid in the tube assembly 10, the low-temperature fluid in the fluid channel A is used for outward transportation, and the low-temperature fluid in the cooling channel B will pass through the corresponding outer wall of the fluid channel A during the circulation process to exchange heat with the tube assembly 10, and the low-temperature fluid in the cooling channel B after heat exchange with the tube assembly 10 can be discharged to the atmosphere in time until the temperature of the outer wall of the fluid channel A is consistent or nearly consistent with the temperature of the low-temperature fluid in the fluid channel A, which reduces the temperature difference between the low-temperature fluid in the fluid channel A and the outer wall of the fluid channel A, thereby suppressing the gasification phenomenon of the low-temperature fluid in the fluid channel A, and further improving the flow control accuracy of the low-temperature fluid at the outlet of the fluid channel A. In addition, based on the cooperation of the fluid channel A and the cooling channel B, the amount of insulation material can be reduced, so that the overall structure of the low-temperature cavitation venturi tube 100 is more compact, and can be used in a more compact system, such as in aerospace.

[0039] Figure 4 This is a schematic diagram of the internal flow channel structure of a low-temperature cavitation venturi provided in an embodiment of the present application, wherein the direction of the arrow in the figure represents the flow direction of the low-temperature fluid.

[0040] See also 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 .

[0041] The main pipe body 11 is the main structure of the pipe body assembly 10 , and is formed with a first connecting channel A2 and a second liquid outlet channel B3 .

[0042] The inlet end tube body 12 is mounted on the main tube body 11 and is sealed and connected to the main tube body 11. For example, a sealing structure such as a sealing ring can be provided between the inlet end tube body 12 and the main tube body 11. The inlet end tube body 12 is formed with a first liquid inlet channel A1, which is connected to the first connecting channel A2. The first liquid inlet channel A1 is used to receive the cryogenic fluid and transport the received cryogenic fluid to the first connecting channel A2.

[0043] The outlet end tube body 13 is installed on the main body 11 and is sealed and connected with the main body 11. For example, a sealing structure such as a sealing ring can be provided between the outlet end tube body 13 and the main body 11. The outlet end tube body 13 is formed with a first liquid outlet channel A3 and a second connecting channel B2. The first liquid outlet channel A3 is connected with the first connecting channel A2. The first liquid outlet channel A3 is used to transport the low-temperature fluid outward. The second connecting channel B2 is provided on at least part of the outer wall of the first liquid outlet channel A3. In addition, the outlet end tube body 13 and the main body 11 are formed with a second liquid inlet channel B1. The second liquid inlet channel B1 is connected with the second connecting channel B2. The second liquid inlet channel B1 is used to receive the low-temperature fluid and transport the received low-temperature fluid to the second connecting channel B2.

[0044] Among them, the first liquid inlet channel A1, the first connecting channel A2 and the first liquid outlet channel A3 are connected in sequence to form a fluid channel A, the second liquid inlet channel B1, the second connecting channel B2 and the second liquid outlet channel B3 are connected in sequence to form a cooling channel B, and the second liquid inlet channel B1 is connected to the first connecting channel A2.

[0045] 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 mutually connected fluid channels A and cooling channels B on the main pipe body 11, the inlet end pipe body 12 and the outlet end pipe body 13 and arranging the second connecting channel B2 of the cooling channel B on at least a portion of the outer wall 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 connecting 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 connecting channel B2 and the second liquid outlet channel B3 and is discharged into the atmosphere, and the other path is transported to other mechanisms of the chemical machinery through the second liquid outlet channel B3, thereby realizing the transportation of the low-temperature fluid in the chemical machinery and the cooling of the outlet end pipe body 13 by the low-temperature fluid, thereby reducing the temperature difference between the outlet end pipe body 13 and the low-temperature fluid therein, thereby suppressing the gasification phenomenon of the low-temperature fluid in the outlet end pipe body 13, and thereby improving the flow control accuracy of the low-temperature fluid at the outlet of the outlet end pipe body 13. Furthermore, 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 interconnecting the fluid channel A and the cooling channel B through the corresponding parts, the structures of the fluid channel A and the cooling channel B are made compact, and the space utilization rate on the pipe body assembly 10 is improved, so that the low-temperature cavitation venturi 100 of the present application can be used in a more compact system.

[0046] Figure 5 This is a schematic diagram of the internal flow channel structure of the outlet end tube body provided in an embodiment of the present application.

[0047] See also Figure 4 and Figure 5 The first liquid outlet channel A3 includes a contraction section flow channel A31, a throat flow channel A32 and an expansion section flow channel A33 which are sequentially connected along the axial direction C thereof, and the contraction 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. In other words, the contraction section flow channel A31, the throat flow channel A32 and the expansion 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.

[0048] It should be noted that, since the contraction section flow channel A31, the throat flow channel A32 and the expansion section flow channel A33 of the first liquid outlet channel A3 are sequentially connected and arranged along the flow direction of the low-temperature fluid, after the low-temperature fluid enters the first connecting channel A2 from the first liquid inlet channel A1, the low-temperature fluid reaching the first liquid outlet channel A3 will first enter the contraction section flow channel A31 to accelerate. According to the Bernoulli principle, the increase in fluid velocity will cause its static pressure to drop. When the static pressure drops below the saturated vapor pressure of the low-temperature fluid, cavitation will occur in the tube. 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, but not 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 first gap opening formed by the valve core 20 and the inner wall of the throat flow channel A32) can be adjusted to achieve flow control in the first liquid outlet channel A3, thereby ensuring that the cavitation of the low-temperature fluid in the first liquid outlet channel A3 is more sufficient and the stability of the flow is improved. Finally, the low-temperature fluid passes through the throat flow channel A32 and then decelerates through the expansion section flow channel A33 to increase the static pressure of the low-temperature fluid, so that the evaporated fluid condenses again after the static pressure of the low-temperature fluid is greater than its saturated vapor pressure and flows out from the outlet of the expansion section flow channel A33.

[0049] In this embodiment, since the second connecting 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, the low-temperature fluid in the cooling channel B can exchange heat with the outer wall of the throat flow channel A32 when flowing through the second connecting channel B2, thereby greatly reducing the temperature of the portion of the tube body assembly 10 forming the throat flow channel A32, which reduces the temperature difference between the low-temperature fluid in the throat flow channel A32 and the portion of the tube body assembly 10 forming the throat flow channel A32, thereby suppressing the vaporization 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.

[0050] See also Figure 3 , Figure 4 and Figure 5The valve core 20 includes a main body 21 and an adjusting part 22. One end of the main body 21 is connected to the driving mechanism 30, and the other end is connected to the adjusting part 22. At least part of the adjusting part 22 is formed into a conical structure. For example, the adjusting part 22 is formed into a conical structure as a whole or one end of the adjusting part 22 away from the main body 21 is formed into a conical structure. This is not specifically limited in this application. The main body 21 can drive the adjusting part 22 to reciprocate in the axial direction 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 in the throat flow channel A32 of the first liquid outlet channel A3.

[0051] Based on the fact that at least part of the regulating portion 22 is formed into a conical structure, under the action of the driving mechanism 30, different parts of the regulating portion 22 can enclose first gaps of different opening sizes with the throat flow channel A32 of the first liquid outlet channel A3, thereby achieving control of the flow area of ​​the throat flow channel A32. In addition, the present application can achieve the size adjustment of the flow area of ​​the throat flow channel A32 by controlling the movement of the valve core 20 through the driving mechanism 30, which has a simple structure, high precision, and good practicality.

[0052] See also Figure 3 and Figure 4 The second liquid outlet channel B3 includes a mounting section B31, a regulating section B32 and a discharge section B33 which are interconnected, and the outlet end of the discharge section B33 is used to communicate with the atmospheric environment. The low-temperature cavitation venturi 100 also includes an adjusting component 40, which is connected to the mounting section B31, and a portion of the adjusting component 40 and the inner wall of the regulating section B32 form a second gap with an adjustable opening to adjust the flow of the fluid entering the discharge section B33.

[0053] Since part of the regulating component 40 can form a second gap with adjustable opening together with the inner wall of the regulating section B32, the fluid flow entering the discharge section B33 can be adjusted based on the change in the opening of the second gap, thereby ensuring the stability of the flow of the low-temperature fluid at the outlet of the first liquid outlet channel A3.

[0054] In some embodiments, the adjusting component 40 and the main body 11 are made of materials with different expansion rates, and the expansion degree of the main body 11 under the temperature difference with the cryogenic fluid is greater than the expansion degree of the adjusting component 40 under the temperature difference with the cryogenic fluid (correspondingly, the contraction degree of the main body 11 under the temperature difference with the cryogenic fluid is greater than the contraction degree of the adjusting component 40 under the temperature difference with the cryogenic fluid) to adjust the opening of the second gap enclosed by the adjusting component 40 and the inner wall of the adjusting section B32.

[0055] It can be understood that in order to ensure that the expansion degree of the main body 11 under the temperature difference with the low-temperature fluid is greater than the expansion degree of the adjusting component 40 under the temperature difference with the low-temperature fluid, the adjusting component 40 can be made of a low-expansion rate material (such as a metal material) and the main body 11 can be made of a high-expansion rate material (such as a metal material).

[0056] Since the regulating component 40 and the main 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 body 11 and the low-temperature fluid inside it is the largest. Since the expansion degree of the main body 11 under the temperature difference with the low-temperature fluid is greater than the expansion degree of the regulating component 40 under the temperature difference with the low-temperature fluid, the opening of the second gap formed by the regulating component 40 and the inner wall of the regulating 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 body 11 and the low-temperature fluid inside it gradually decreases, the main body 11 and the regulating component 40 begin to gradually shrink, and the opening of the second gap formed by the regulating component 40 and the inner wall of the regulating section B32 gradually decreases, so that the fluid flow rate entering the discharge section B33 gradually decreases; and when the temperature of the main body 11 and the regulating component 40 is close to that of the low-temperature fluid (the temperature difference is the smallest), the shrinkage degree of the main body 11 and the regulating component 40 is the largest, so that the opening of the second gap is the smallest (close to being closed), so that the fluid flow rate entering the discharge section B33 is the smallest.

[0057] Therefore, since the regulating component 40 and the main body 11 are made of materials with different expansion rates, the opening of the second gap formed by the regulating component 40 and the inner wall of the regulating section B32 can adaptively increase with the increase of the temperature difference and decrease with the decrease of the temperature difference, so that the fluid flow entering the discharge section B33 can be regulated without manual or electric cylinder adjustment, thereby ensuring the stability of the flow of the low-temperature fluid at the outlet of the first liquid outlet channel A3, and the structure is simple and the reliability is high.

[0058] Figure 6 A schematic diagram of a structure of an adjustment component provided in an embodiment of the present application is also Figure 3 Enlarged view of the circled area.

[0059] In some embodiments, see Figure 3 and Figure 6 The adjusting component 40 includes an adjusting screw 41, and 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 mounting section B31, and at least part of the matching section 412 is formed into a conical structure. The connecting section 411 is configured to be able to move relative to the mounting section B31 under the action of an external force, so that different parts of the matching section 412 can form a second gap with different openings with the inner wall of the adjusting section B32.

[0060] In this embodiment, based on the threaded connection between the connecting section 411 of the adjusting screw 41 and the inner wall of the mounting section B31, the depth of the connecting section 411 of the adjusting screw 41 screwed into the mounting section B31 can be manually adjusted by using a tool. After the throat flow channel A32 is cooled to the right position by the low-temperature fluid in the cooling channel B, the adjusting screw 41 can be screwed clockwise to reduce the opening of the second gap formed by the matching section 412 and the inner wall of the adjusting section B32, and the flow rate is small; and when the temperature difference is large, the adjusting screw 41 is screwed counterclockwise to increase the opening of the second gap formed by the matching section 412 and the inner wall of the adjusting section B32, and the flow rate is increased. Therefore, by controlling the adjusting screw 41 to screw in or out of the mounting section B31, different parts of the matching section 412 can form second gaps with different openings with the inner wall of the adjusting section B32, thereby controlling the fluid flow entering the discharge section B33, thereby improving the cooling efficiency of the low-temperature fluid in the cooling channel B on the outlet end pipe body 13.

[0061] Figure 7 A schematic diagram of the structure of another adjusting component provided in an embodiment of the present application.

[0062] In some embodiments, see Figure 7 The adjusting component 40 includes an adjusting screw 41 and a servo electric cylinder 42. 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 mounting section B31, and at least part of the matching section 412 is formed into a conical structure. 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 mounting section B31, so that different parts of the matching section 412 can form a second gap with different openings with the inner wall of the adjusting section B32.

[0063] The servo electric cylinder 42 drives the connecting section 411 to move to adjust the depth of the connecting section 411 screwed into the mounting section B31, which can further improve the cooling efficiency of the low-temperature fluid in the cooling channel B on the outlet pipe body 13.

[0064] Furthermore, the adjusting component 40 also 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 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 to adjust the opening of the second gap enclosed by the fitting section 412 and the inner wall of the adjusting section B32.

[0065] Specifically, through the pre-set data relationship between the temperature of the main body 11 and the opening of the second gap, when the temperature difference between the main body 11 and the cryogenic fluid is too large, the servo electric cylinder 42 is feedback-regulated to increase the opening of the second gap; when the temperature difference is small, the servo electric cylinder 42 is regulated to reduce the opening of the second gap. Therefore, based on the monitored temperature data of the part of the main body 11 forming the adjustment section B32, the servo electric cylinder 42 can be closed-loop controlled and regulated, thereby realizing the fully automatic adjustment of the opening of the second gap, thereby further improving the cooling efficiency of the low-temperature fluid in the cooling channel B on the outlet end tube body 13. In addition, based on the improvement of the cooling efficiency of the low-temperature fluid in the cooling channel B on the outlet end tube body 13, the discharge of the low-temperature fluid into the atmosphere through the cooling channel B can be reduced.

[0066] In some embodiments, see Figures 1 to 3 A portion of the main body 11 close to the driving mechanism 30 is formed with a plurality of heat exchange fins 111 .

[0067] In this embodiment, by providing a plurality of heat exchange fins 111 on the main body 11, during the operation of the low-temperature cavitation venturi 100, the air in the atmospheric environment can exchange heat with the plurality of heat exchange fins 111, thereby increasing the area of ​​the heat exchange surface of the main body 11 to increase the temperature of the end of the main body 11 close to the driving mechanism 30, thereby avoiding the influence of the excessively low temperature of the main body 11 on the driving mechanism 30.

[0068] In some embodiments, see 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, so as to drive the valve core 20 to reciprocate along the axial direction C.

[0069] In some embodiments, please refer to Figures 1 to 3 The driving motor 31 includes a motor body 311 and a motor shaft 312 extending out of the motor body 311. The driving mechanism 30 also includes a mounting frame 34, an adapter 35, a position-limiting connector 36, a position-limiting bearing 37 and a position-limiting optical axis 38.

[0070] The mounting frame 34 is located between the motor tube body 311 and the tube body assembly 10 in the axial direction C, the limit connecting piece 36 is connected to the adapter 35 and the valve core 20, the limit bearing 37 is arranged on the limit connecting piece 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 axial direction C.

[0071] Specifically, the limit connecting member 36 can be connected to the limit bearing 37 by screws, and 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 constrain the reciprocating motion of the limit connecting member 36 along the axial direction C.

[0072] In some embodiments, see Figure 3 The low-temperature cavitation venturi 100 of the present application further includes a sealing component 50 , which is disposed between the regulating portion 22 of the valve core 20 and the main pipe body 11 , and is used to seal and connect the valve core 20 and the main pipe body 11 .

[0073] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. Those skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A low temperature cavitation venturi, characterized in that: include: A tube body assembly (10) is formed with a fluid channel (A) and a cooling channel (B); A valve core (20) at least partially disposed in the fluid channel (A); as well as 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 channel (A), so as to adjust the opening of a first gap formed by the valve core (20) and the inner wall of the fluid channel (A), so as to adjust the fluid flow in the fluid channel (A); Wherein, at least a portion 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 used to communicate with the atmospheric environment.

2. The low temperature cavitation venturi according to claim 1, characterized in that: The pipe body assembly (10) comprises: A main body (11) formed with a first connecting channel (A2) and a second liquid outlet channel (B3); An inlet end pipe body (12) is mounted on the main pipe body (11) and is formed with a first liquid inlet channel (A1); and an outlet end tube body (13) mounted on the main tube body (11) and forming a first liquid outlet channel (A3) and a second connecting channel (B2); the outlet end tube body (13) and the main tube body (11) together form a second liquid inlet channel (B1); the second connecting channel (B2) is arranged on at least a portion of the outer wall of the first liquid outlet channel (A3); The first liquid inlet channel (A1), the first connecting channel (A2) and the first liquid outlet channel (A3) are connected in sequence to form the fluid channel (A); the second liquid inlet channel (B1), the second connecting channel (B2) and the second liquid outlet channel (B3) are connected in sequence to form the cooling channel (B); and the second liquid inlet channel (B1) is connected to the first connecting channel (A2).

3. The low temperature cavitation venturi according to claim 2, characterized in that: The first liquid outlet channel (A3) comprises a contraction section flow channel (A31), a throat flow channel (A32) and an expansion section flow channel (A33) which are sequentially connected along the axial direction (C), and the contraction section flow channel (A31) is located on a side of the throat flow channel (A32) close to the first connecting channel (A2) in the axial direction (C); The second connecting channel (B2) is at least arranged on the outer wall of the throat flow channel (A32).

4. The low temperature cavitation venturi according to claim 2, characterized in that: The second liquid outlet channel (B3) comprises a mounting section (B31), a regulating section (B32) and a discharge section (B33) which are interconnected, and the outlet end of the discharge section (B33) is used to communicate with the atmospheric environment; The low-temperature cavitation venturi further comprises an adjusting component (40), the adjusting component (40) being connected to the mounting section (B31), and a portion of the adjusting component (40) and an inner wall of the adjusting section (B32) enclosing a second gap with an adjustable opening, so as to adjust the flow rate of the fluid entering the discharge section (B33).

5. The low temperature cavitation venturi according to claim 4, characterized in that: The regulating component (40) and the main pipe (11) are made of materials with different expansion rates, and the expansion degree of the main pipe (11) under the action of the temperature difference between the main pipe and the fluid is greater than the expansion degree of the regulating component (40) under the action of the temperature difference between the main pipe and the fluid, so as to adjust the opening of the second gap formed by the regulating component (40) and the inner wall of the regulating section (B32).

6. The low temperature cavitation venturi according to claim 4, characterized in that: The adjusting component (40) comprises an adjusting screw (41), the adjusting screw (41) comprising a connecting section (411) and a matching section (412), the connecting section (411) being threadedly connected to an inner wall of the mounting section (B31), and at least a portion of the matching section (412) being formed into a conical structure; The connecting section (411) is configured to be able to move relative to the mounting section (B31) under the action of an external force, so that different parts of the matching section (412) can enclose the second gap with the inner wall of the adjustment section (B32).

7. The low temperature cavitation venturi according to claim 6, characterized in that: The adjusting component (40) further comprises a servo electric cylinder (42), wherein 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) being screwed into the mounting section (B31).

8. The low temperature cavitation venturi according to claim 7, characterized in that: The regulating component (40) further comprises a measuring unit and a control unit, wherein the measuring unit is used to monitor the temperature of a portion of the main body (11) forming the regulating 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 of the second gap formed by the inner wall of the matching section (412) and the adjusting section (B32).

9. The low temperature cavitation venturi according to any one of claims 2 to 8, characterized in that: The valve core (20) comprises a main body (21) and an adjusting portion (22), the main body (21) being connected to the driving mechanism (30), at least a portion of the adjusting portion (22) being formed into a conical structure, and the main body (21) being capable of driving the adjusting portion (22) to reciprocate in the axial direction (C) relative to the first liquid outlet channel (A3) under the action of the driving mechanism (30) so as to adjust the flow rate of the fluid in the first liquid outlet channel (A3); and / or A heat exchange fin structure (111) is formed on a portion of the main pipe (11) close to the driving mechanism (30); and / or The driving mechanism (30) comprises 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) via the coupling (33), and the other end is connected to the valve core (20) via the adapter (35); and the ball screw (32) is used to convert the rotational motion of the driving motor (31) into the linear motion of the adapter (35), so as to drive the valve core (20) to reciprocate along the axial direction (C).

10. The low temperature cavitation venturi according to claim 9, characterized in that: The driving motor (31) comprises a motor tube body (311) and a motor shaft (312) extending out of the motor tube body (311); The driving mechanism (30) further comprises: a mounting frame (34) located between the motor tube body (311) and the tube body assembly (10) in the axial direction (C); a limit connecting piece (36) connected to the adapter (35) and the valve core (20); a limit bearing (37) disposed on the limit connecting piece (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 used to abut against the limit bearing (37) to limit the movement of the limit bearing (37) in the axial direction (C).

11. A flow control device for chemical machinery, characterized in that: Comprising the low-temperature cavitation venturi (100) as described in any one of claims 1 to 10.

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