GB2608721A

GB2608721A - Flow-adaptive guide vane adjustment device based on hydraulic transmission

Info

Publication number: GB2608721A
Application number: GB2212248.5A
Authority: GB
Inventors: Li Hul; Zhou Ling; Shi Weidong; Xue Peng; Han Yong; Li Wei; Chang Hao; Zhu Yong
Original assignee: Jiangsu University
Current assignee: Jiangsu University
Priority date: 2021-04-28
Filing date: 2021-06-16
Publication date: 2023-01-11
Anticipated expiration: 2041-06-16
Also published as: WO2022227244A1; CN113153821B; CN113153821A; GB202212248D0; GB2608721B

Abstract

A flow-adaptive guide vane adjustment device based on hydraulic transmission. The device mainly comprises a Venturi pipe (1), a hydraulic cylinder (2), a cam mechanism and hydraulic pipes (4), which are used in cooperation with a pump and a movable guide vane adjustment mechanism. The Venturi pipe (1) is mounted at an outlet of the pump, and an inlet section (11) and a throat part (13) of the Venturi pipe (1) are subjected to pressure measurement, and are connected to two sides of the hydraulic cylinder (2) by means of the hydraulic pipes (4). The hydraulic cylinder (2) internally comprises a double-rod piston (23) and a spring (29), the spring (29) being mounted on a piston rod (21). The exterior of the piston rod (21) is connected to the form-closed translating cam mechanism, and a follower (33) of the cam mechanism is connected to the movable guide vane adjustment mechanism. The pressure of two sides of the piston (23) changes with a flow change; thus, the elongation of the spring (29) changes, and the cam mechanism is driven to translate. Then, the movable guide vane adjustment mechanism acts by means of the follower (33), such that the angle of a guide vane is automatically adjusted with the flow of the pump, thereby reducing the impact loss of an off-design condition, broadening a high-efficiency area of the pump, and achieving the aims of efficiency improvement and energy conservation.

Description

FLOW-ADAPTIVE GUIDE VANE ADJUSTMENT DEVICE

BASED ON HYDRAULIC TRANSMISSION C\J C\I

TECH ICAL FIELD

The present disclosure belongs to the technical field of water pumps, and in particular, relates to a flow self-adaptive guide vane adjustment apparatus based on hydraulic transmission [SAC ICG 0 UN D As a type of general-purpose machine, pumps are widely used in various fields of the national economy. According to statistics, the power consumption of pumps accounts for about 20% of the total electric energy production of China. Vane pumps include centrifugal pumps, mixed flow pumps, axial flow pumps, and the like, and are the most widely used pumps because of various advantages such as wide ranges of flow and lift, a uniform flow, a simple structure, and an easy operation. Therefore, it is of great significance to improve the efficiency of vane pumps, reduce energy consumption, save energy, and reduce emissions.

In actual engineering, operating conditions are complex and changeful, when a. vane pump deviates from a design condition, a vane inlet placement angle of an impeller and a guide vane is inconsistent with a fluid flow angle of an incoming flow, which increases the impact loss, destroys the flow stability, and reduces the operation efficiency.

In order to improve the efficiency of a non-design condition and widen a high-efficiency area of a pump, a commonly used method is installing a movable guide vane in front of an impeller inlet or behind an impeller outlet, and adjusting an angle of the movable guide vane to reduce the turbulence loss caused by inconsistency between the fluid flow angle and the vane placement angle, thereby reducing the hydraulic loss to improve the pump efficiency and stability. However, the adjustment of the opening of the movable guide vane is performed manually depending on experiences, the adjustment has a large workload and a low degree of automation, and it is difficult to perform adjustment in real time according to changes in operating conditions. In some other methods, real-time adjustment according to the flow is realized by using a module such as a flow monitoring unit, a single-chip control unit, a stepper motor, and an angle sensor, so that the guide vane is at an optimal opening under different flow rates, thereby improving the operating efficiency of the pump. However, the technical route is complicated and auxiliary devices are numerous, thus having a high cost and low reliability.

SUMMARY

An objective of the present disclosure is to solve the problems in the prior art that a pump without a movable guide vane has a low efficiency under a non-design condition, and an automatic adjustment apparatus of a pump with a movable guide vane is complicated and low in reliability.

In order to achieve the above objective, the present disclosure provides a flow self-adaptive guide vane adjustment apparatus based on hydraulic transmission, including a venturi tube, a hydraulic cylinder, and hydraulic tubes; the venturi tube includes an inlet section, a constriction section, a throat, and a diffusion section; the inlet section and the throat are respectively provided with an inlet section interface and a throat interface; the hydraulic cylinder includes a cylinder body, a piston, a piston rod, and a spring; the piston rod and the piston are assembled into a whole; the piston is installed in the cylinder body, two ends of the piston rod respectively extend through two ends of the cylinder body and protrude to an outside of the cylinder body, the piston and the piston rod are configured to reciprocate linearly along an axis of the cylinder body; two sides of the cylinder body are further respectively provided with a first hydraulic cylinder interface and a second hydraulic cylinder interface, an inner portion of the first hydraulic cylinder interface and an inner portion of the second hydraulic cylinder interface are respectively in communication with a first hydraulic cylinder cavity and a second hydraulic cylinder cavity, and an outer portion of the first hydraulic cylinder interface and an outer portion of the second hydraulic cylinder interface are respectively in communication with the inlet section and the throat interface through the hydraulic tubes; the spring is installed on the piston rod; changes in a flow cause changes in a pressure difference between the inlet section interface and the throat interface, and the pressure difference is transmitted to two sides of the piston, causing the piston and the rod to move along the axis of the cylinder to change an extension and contraction amount of the spring, so that the piston and the piston rod reach a new equilibrium position.

Further, the flow self-adaptive guide vane adjustment apparatus based on the hydraulic transmission according to the present disclosure further includes a pump and a movable guide vane adjustment mechanism; the pump includes an impeller, a pump body, and a shaft; the venturi tube is installed at an outlet of the pump, the hydraulic cylinder is fixed in a position relative to the pump, and the movable guide vane adjustment mechanism is installed on the pump; the piston rod is connected to the movable guide vane adjustment mechanism, and a movement of the piston rod is configured to be transmitted to a movable guide vane through the movable guide vane adjustment mechanism, so as to realize adjustment of an opening of the movable guide vane.

Further, the flow self-adaptive guide vane adjustment apparatus based on the hydraulic transmission according to the present disclosure further includes a cam mechanism, and the cam mechanism includes a cam, a follower, and a rack; the cam is connected to the piston rod; the cam is a form-closed moving cam and provided with a groove thereon; the follower is arranged in the rack, and the rack restricts a movement of the follower, so that the follower is configured to reciprocate linearly in only one direction; a roller is provided at an end of the follower, and the roller is arranged in the groove of the cam; the movement of the piston rod drives the cam to move, and causes the follower to reciprocate linearly in the direction restricted by the rack.

Further, the flow self-adaptive guide vane adjustment apparatus based on the hydraulic transmission according to the present disclosure further includes a pump and a movable guide vane adjustment mechanism; the pump includes an impeller, a pump body, and a shaft; the venturi tube is installed at an outlet of the pump, the hydraulic cylinder is fixed in a position relative to the pump, and the movable guide vane adjustment mechanism is installed on the pump; the follower of the cam mechanism is connected to the movable guide vane adjustment mechanism, and the movement of the follower is configured to be transmitted to a movable guide vane through the movable guide vane adjustment mechanism, so as to realize an adjustment of an opening of the movable guide vane.

The movable guide vane is installed in front of an inlet of the impeller of the pump, and/or installed behind an outlet of the impeller of the pump.

Further, the inlet section interface includes a pressure tap arranged on a wall surface of the inlet section, and the pressure tap is perpendicular to a flow direction to obtain a static pressure of the inlet section.

Further, the inlet section interface includes a pressure tap extending into a center of the inlet section through an elbow, and the pressure tap faces a direction of an incoming flow to obtain a total pressure of the inlet section.

Further, one or more flow self-adaptive guide vane adjustment apparatuses based on hydraulic transmission are provided.

Further, the pump is a centrifugal pump, a mixed flow pump, or an axial flow pump.

A working principle of the present disclosure is as follows.

When the flow rate changes, the pressure difference between the inlet section and the throat of the venturi tube changes, and the pressure is transmitted to two sides of the piston of the hydraulic cylinder through the hydraulic tubes, so that a hydraulic pressure subjected by the piston changes, and the hydraulic pressure of the piston is balanced by the spring, causing changes in the position of the piston. Then, the guide vane is rotated by the piston rod, the cam mechanism, and the guide vane adjustment mechanism, so as to realize automatic adjustment of the opening of the guide vane, so that the adjustment of the opening of the guide vane has a characteristic of flow self-adaptation.

The present disclosure has the following beneficial effects.

(1) The present disclosure can automatically adjust the opening of the guide vane according to the flow rate of the pump. When the guide vane is located in front of the inlet of the impeller, a flow pre-swirl can be changed by adjusting the angle of the guide vane to reduce an impact loss at the inlet of the impeller under different conditions; when the guide vane is located behind the outlet of the impeller, adjusting the angle of the guide value can reduce an angle of attack at an inlet of the guide vane under different conditions, and reduce the hydraulic loss, thereby improving the operating efficiency of the pump under a non-design condition, and widening the high-efficiency operating range of the pump.

(2) Modules such as sensors and controllers are not required, and therefore, the structure is simple and high in reliability.

(3) The liquid pressure energy at the outlet of the pump is used as the energy of the guide vane adjustment mechanism, no additional power source is required, and it is simple and efficient.

(4) Hydraulic transmission is adopted, which can amplify the liquid pressure to obtain sufficient power.

(5) When the cam mechanism is used, as long as a profile of the cam is properly designed, the adjustment of the opening of the guide vane can meet an expected adjustment law.

(6) It is widely applied and can be used for automatic adjustment of a movable guide vane of a centrifugal pump, a mixed flow pump, and an axial flow pump.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of Embodiment 1 of a flow self-adaptive guide vane adjustment apparatus based on hydraulic transmission according to the present disclosure.

FIG. 2 is a top view of Embodiment I of a flow self-adaptive guide vane adjustment apparatus based on hydraulic transmission according to the present disclosure.

FIG. 3 is a cross-sectional view of Embodiment 1 of a flow self-adaptive guide vane adjustment apparatus based on hydraulic transmission according to the present disclosure along A-A.

FIG. 4 is a cross-sectional view of Embodiment 1 of a flow self-adaptive guide vane adjustment apparatus based on hydraulic transmission according to the present disclosure along B-B.

FIG. 5 is a schematic view of a pressure tap of an inlet section interface facing a direction of an incoming flow.

FIG. 6 is a schematic view of a pressure tap of an inlet section interface being perpendicular to a direction of an incoming flow.

FIG. 7 is a schematic structural view of a form-closed moving cam mechanism.

FIG. 8 is a schematic structural view of a hydraulic cylinder.

FIG. 9 is a schematic view of Embodiment 2 of a flow self-adaptive guide vane adjustment apparatus based on hydraulic transmission according to the present disclosure.

FIG. 10 is a partial enlarged view of Embodiment 2 of a flow self-adaptive guide vane adjustment apparatus based on hydraulic transmission according to the present disclosure.

FIG. 11 is a schematic view of Embodiment 3 of a flow self-adaptive guide vane adjustment apparatus based on hydraulic transmission according to the present disclosure.

In the drawings: 1-Venturi tube; 11-Inlet section; 12-Constriction section; 13-Throat; 14-Diffusion section; 15-Inlet section interface; 16-Throat interface; 17-Inlet section tee-junction; 18-Throat tee-junction; 2-Hydraulic cylinder; 21-Piston rod; 23-Piston; 24-Cylinder body; 25-First hydraulic cylinder interface; 26-Second hydraulic cylinder interface; 27-First hydraulic cylinder cavity; 28-Second hydraulic cylinder cavity; 29-Spring; 3-Cam; 31-Cam groove; 32-Roller; 33-Follower; 34-Rack; 35-Push-pull rod; 4-Hydraulic tube; 5-Pump body; 6-Guide vane chamber; 61-Guide vane shaft; 62-Driven bevel gear; 63-Gear rack; 64-Gear; 65-Bevel gear plate; 66-Front guide vane; 67-Gear shaft; 68-Driving bevel gear; 7-Impeller; 8-Shaft; 9-Pump cover; 101-Control ring; 102-Connecting arm; 103-Guide vane sleeve; 104-Guide vane shaft; and 105-Guide vane.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The present disclosure will be further described below with reference to the accompanying drawings and embodiments.

Embodiment 1: As shown in FIG. 1 and FIG. 2, there is one flow self-adaptive guide vane adjustment apparatus based on hydraulic transmission according to the present disclosure, including a venturi tube 1, a hydraulic cylinder 2, and hydraulic tubes 4. The venturi tube 1 includes an inlet section 11, a constriction section 12, a throat 13, and a diffusion section 14. The inlet section 11 and the throat 13 are respectively provided with an inlet section interface 15 and a throat interface I 6.

As shown in FIG. 8, the hydraulic cylinder 2 includes a cylinder body 24, a piston 23, a piston rod 21, and a spring 29. The piston rod 21 and the piston 23 are assembled into a whole. The piston 23 is installed in the cylinder body 24 to divide the space in the cylinder body 24 into a first hydraulic cylinder cavity 27 and a second hydraulic cylinder cavity 28. Two ends of the piston rod 21 respectively extend through two ends of the cylinder body 24 and protrude to an outside of the cylinder body 24. The piston 23 and the piston rod 21 are configured to reciprocate linearly along an axis of the cylinder body 24. Two sides of the cylinder body 24 are further respectively provided with a first hydraulic cylinder interface 25 and a hydraulic cylinder second interface 26. The inner portion of the first hydraulic cylinder interface 25 and the inner portion of the second hydraulic cylinder interface 26 are respectively in communication with the first hydraulic cylinder cavity 27 and the second hydraulic cylinder cavity 28, and the outer portion of the first hydraulic cylinder interface 25 and the outer portion of the second hydraulic cylinder interface 26 are respectively in communication with the inlet section interface 15 and the throat interface 16 through the hydraulic tubes 4. The spring 29 is installed on the piston rod 21. Changes in the flow will cause changes in a pressure difference between the inlet section interface 15 and the throat interface 16, and the pressure difference is transmitted to two sides of the piston 23 through the hydraulic tubes 4, causing the piston 23 and the piston rod 21 to move along the axis of the cylinder body 24 to change the extension and contraction amount of the spring 29, so that the piston 23 and the piston rod 21 reach a new equilibrium position.

As shown in FIG. 7, the present disclosure further includes a cam mechanism, and the cam mechanism includes a cam 3, a follower 33, and a rack 34. The cam 3 is connected to the piston rod 21. The cam 3 is a form-closed moving cam and provided with a groove 31 thereon. The follower 33 is arranged in the rack 34, and the rack 34 restricts the movement of the follower 33, so that the follower 33 is configured to reciprocate linearly in only one direction. A roller 32 is provided at an end of the follower 33, and the roller 32 is arranged in the cam groove 31. The movement of the piston rod 21 will drive the cam 3 to move, and cause the follower 33 to reciprocate linearly in the direction restricted by the rack 34.

The present disclosure further includes a pump and a movable guide vane adjustment mechanism. The pump is a centrifugal pump, and includes an impeller 7, a pump body 5, a shaft 8, and a pump cover 9. The venturi tube 1 is installed at an outlet of the pump, and the hydraulic cylinder 2 is fixed in a position relative to the pump. The movable guide vane adjustment mechanism is installed in front of an inlet of the impeller 7, and mainly consists of a gear rack 63, a gear 64, a gear shaft 67, a driving bevel gear 68, a bevel gear plate 65, a driven bevel gear 62, a guide vane shaft 61, front guide vanes 66, and a guide vane chamber 6, and the number of the front guide vanes 66 is 6. The follower 33 of the cam mechanism is connected to the gear rack 63, and the gear rack 63 is engaged to the gear 64 and drives the driving bevel gear 68 and the front guide vanes 66 to rotate through the gear shaft 67. The driving bevel gear 68 is engaged to the bevel gear plate 65, and drives the bevel gear plate 65 to rotate. The bevel gear plate 65 is engaged to the driven bevel gear 62, drives the driven bevel gear 62 to rotate, and drives the remaining front guide vanes 66 to rotate synchronously through the guide vane shaft 61, so as to adjust the opening of the front guide vanes 66.

As shown in FIG. 5, a pressure tap of the inlet section interface 15 extends into the center of the inlet section 11 through an elbow and faces the direction of an incoming flow, so as to obtain a total pressure of the inlet section 11.

Embodiment 2: As shown in FIG. 9, two flow self-adaptive guide vane adjustment apparatuses based on hydraulic transmission according to the present disclosure are used at the same time, and each include a venturi tube 1, a hydraulic cylinder 2, and hydraulic tubes 4. The venturi tube 1 includes an inlet section II, a constriction section 12, a throat 13, and a diffusion section 14. The inlet section 11 and the throat 13 are respectively provided with an inlet section interface 15 and a throat interface 16. An inlet section tee-junction 17 and a throat tee-junction 18 are respectively installed at an outer portion of the inlet section interface 15 and an outer portion of the throat interface 16. As shown in FIG. 8, the hydraulic cylinder 2 includes a cylinder body 24, a piston 23, a piston rod 21, and a spring 29. The piston rod 21 and the piston 23 are assembled into a whole. The piston 23 is installed in the cylinder body 24 to divide the space in the cylinder body 24 into a first hydraulic cylinder cavity 27 and a second hydraulic cylinder cavity 28. Two ends of the piston rod 21 respectively extend through two ends of the cylinder body 24 and protrude to an outside of the cylinder body 24. The piston 23 and the piston rod 21 are configured to reciprocate linearly along an axis of the cylinder body 24. Two sides of the cylinder body 24 are further respectively provided with a first hydraulic cylinder interface 25 and a hydraulic cylinder second interface 26.

The inner portion of the first hydraulic cylinder interface 25 and the inner portion of the second hydraulic cylinder interface 26 are respectively in communication with the first hydraulic cylinder cavity 27 and the second hydraulic cylinder cavity 28, and the outer portion of the first hydraulic cylinder interface 25 and the outer portion of the second hydraulic cylinder interface 26 are respectively in communication with the inlet section tee-junction 17 and the throat tee junction 18 through the hydraulic tubes 4. The spring 29 is installed on the piston rod 21. Changes in the flow will cause changes in a pressure difference between the inlet section tee-junction 17 and the throat tee-junction 18, and the pressure difference is transmitted to two sides of the piston 23 through the hydraulic tubes 4, causing the piston 23 and the piston rod 21 to move along the axis of the cylinder body 24 to change the extension and contraction amount of the spring 29, so that the piston 23 and the piston rod 21 reach a new equilibrium position.

As shown in FIG. 7, the present disclosure further includes a cam mechanism, and the cam mechanism includes a cam 3, a follower 33, and a rack 34. The cam 3 is connected to the piston rod 21. The cam 3 is a form-closed moving cam and provided with a groove 31 thereon. The follower 33 is arranged in the rack 34, and the rack 34 restricts the movement of the follower 33, so that the follower 33 is configured to reciprocate linearly in only one direction. A roller 32 is provided at an end of the follower 33, and the roller 32 is arranged in the groove 31 of the cam. The movement of the piston rod 21 will drive the cam 3 to move, and cause the follower 33 to reciprocate linearly in the direction restricted by the rack 34.

The present disclosure further includes a pump and a movable guide vane adjustment mechanism. The pump is a centrifugal pump, and includes an impeller 7, a pump body 5, a shaft 8, and a pump cover 9. The venturi tube 1 is installed at an outlet of the pump, and the hydraulic cylinder 2 is fixed in a position relative to the pump. The movable guide vane adjustment mechanism is installed behind an outlet of the impeller 7, and mainly consists of a push-pull rod 35, a control ring 101, a connecting arm 102, a guide vane sleeve 103, a guide vane shaft 104, and guide vanes 105, and the number of the guide vanes is 15. One end of the push-pull rod 35 is hinged to the follower 33 of the cam mechanism, and the other end of the push-pull rod 35 is hinged to the control ring 101. One end of the connecting arm 102 is hinged to the control ring 101, and the other end of the connecting arm 102 is hinged to the guide vane sleeve 103. The guide vane sleeve 103 is fixedly connected to the guide vane shaft 104 and the guide vanes 105, and is rotatable around the guide vane shaft 104. The follower 33 of the cam mechanism, when moving, will drive the push-pull rod 35 to move, so as to cause the control ring 101 to rotate, and the guide vane sleeve 103 and the guide vane shaft 104 are driven to rotate by the connecting arm 102, so that all guide vanes 105 rotate synchronously around the guide vane shaft 104, realizing the adjustment of the opening of the guide vanes 105.

As shown in FIG. 5, a pressure tap of the inlet section interface 15 extends into the center of the inlet section 11 through an elbow and faces the direction of an incoming flow, so as to obtain the total pressure of the inlet section 11.

Embodiment 3: As shown in FIG. 11, one flow self-adaptive guide vane adjustment apparatus based on hydraulic transmission according to the present disclosure is provided, including a venturi tube 1, a hydraulic cylinder 2, and hydraulic tubes 4. The venturi tube 1 includes an inlet section 11, a constriction section 12, a throat 13, and a diffusion section 14. The inlet section 11 and the throat 13 are respectively provided with an inlet section interface 15 and a throat interface 16. As shown in FIG. 8, the hydraulic cylinder 2 includes a cylinder body 24, a piston 23, a piston rod 21, and a spring 29. The piston rod 21 and the piston 23 are assembled into a whole. The piston 23 is installed in the cylinder body 24 to divide the space in the cylinder body 24 into a first hydraulic cylinder cavity 27 and a second hydraulic cylinder cavity 28. Two ends of the piston rod 21 respectively extend through two ends of the cylinder body 24 and protrude to an outside of the cylinder body 24. The piston 23 and the piston rod 21 are configured to reciprocate linearly along an axis of the cylinder body 24. Two sides of the cylinder body 24 are further respectively provided with a first hydraulic cylinder interface 25 and a hydraulic cylinder second interface 26. The inner portion of the first hydraulic cylinder interface 25 and the inner portion of the second hydraulic cylinder interface 26 are respectively in communication with the first hydraulic cylinder cavity 27 and the second hydraulic cylinder cavity 28, and the outer portion of the first hydraulic cylinder interface 25 and the outer portion of the second hydraulic cylinder interface 26 are respectively in communication with the inlet section interface 15 and the throat interface 16 through the hydraulic tubes 4. The spring 29 is installed on the piston rod 21. Changes in the flow will cause changes in a pressure difference between the inlet section interface 15 and the throat interface 16, and the pressure difference is transmitted to two sides of the piston 23 through the hydraulic tubes 4, causing the piston 23 and the piston rod 21 to move along the axis of the cylinder body 24 to change the extension and contraction amount of the spring 29, so that the piston 23 and the piston rod 21 reach a new equilibrium position.

The present disclosure further includes a pump and a movable guide vane adjustment mechanism. The pump is a centrifugal pump, and includes an impeller 7, a pump body 5, a shaft 8, and a pump cover 9. The venturi tube 1 is installed at an outlet of the pump, and the hydraulic cylinder 2 is fixed in a position relative to the pump. The movable guide vane adjustment mechanism is installed in front of an inlet of the impeller 7, and mainly consists of a gear rack 63, a gear 64, a gear shaft 67, a driving bevel gear 68, a bevel gear plate 65, a driven bevel gear 62, a guide vane shaft 61, front guide vanes 66, and a guide vane chamber 6, and the number of the front guide vanes 66 is 6. The piston rod 21 is connected to the gear rack 63. The gear rack 63 is engaged to the gear 64 to drive the driving bevel gear 68 and the front guide vanes 66 to rotate through the gear shaft 67. The driving bevel gear 68 is engaged to the bevel gear plate 65 to drive the bevel gear plate 65 to rotate. The bevel gear plate 65 is engaged to the driven bevel gear 62 to drive the driven bevel gear 62 to rotate, and drive the remaining front guide vanes 66 to rotate synchronously through the guide vane shaft 61, realizing the adjustment of the opening of the front guide vanes 66.

As shown in FIG. 6, a pressure tap of the inlet section interface 15 is arranged on a wall surface of the inlet section 11, and is perpendicular to the direction of an incoming flow, so as to obtain a static pressure of the inlet section 11.

The above descriptions are only the embodiments of the present disclosure, and are not intended to limit the patent scope of the present disclosure. Any equivalent structure or equivalent process transformation made by using the contents of the description and accompanying drawings of the present disclosure, or directly or indirectly applied to other related technical fields are similarly included in the patent protection scope of the present disclosure.

Claims

CLAIMSWhat is claimed is: I. A flow self-adaptive guide vane adjustment apparatus based on a hydraulic transmission, comprising a venturi tube (1), a hydraulic cylinder (2), and hydraulic tubes (4), wherein the venturi tube (1) comprises an inlet section (11), a constriction section (12), a throat (13), and a diffusion section (14); the inlet section (I I) and the throat (13) are respectively provided with an inlet section interface (15) and a throat interface (16); and the hydraulic cylinder (2) comprises a cylinder body (24), a piston (23), a piston rod (21), and a spring (29); the piston rod (21) and the piston (23) are assembled into a whole; the piston (23) is installed in the cylinder body (24), two ends of the piston rod (21) respectively extend through two ends of the cylinder body (24) and protrude to an outside of the cylinder body (24), the piston (23) and the piston rod (21) are configured to reciprocate linearly along an axis of the cylinder body (24); two sides of the cylinder body (24) are further respectively provided with a first hydraulic cylinder interface (25) and a second hydraulic cylinder interface (26), an inner portion of the first hydraulic cylinder interface (25) and an inner portion of the second hydraulic cylinder interface (26) are respectively in communication with a first hydraulic cylinder cavity (27) and a second hydraulic cylinder cavity (28), and an outer portion of the first hydraulic cylinder interface (25) and an outer portion of the second hydraulic cylinder interface (26) are respectively in communication with the inlet section interface (15) and the throat interface (16) through the hydraulic tubes (4); the spring (29) is installed on the piston rod (21); changes in a flow cause changes in a pressure difference between the inlet section interface (15) and the throat interface (16), and the pressure difference is transmitted to two sides of the piston (23), causing the piston (23) and the piston rod (21) to move along the axis of the cylinder body (24) to change an extension and contraction amount of the spring (29), so that the piston (23) and the piston rod (21) reach a new equilibrium position.
2. The flow self-adaptive guide vane adjustment apparatus based on the hydraulic transmission according to claim 1, further comprising a pump and a movable guide vane adjustment mechanism, wherein the pump comprises an impeller (7), a pump body (5), and a shaft (8); the venturi tube (1) is installed at an outlet of the pump, the hydraulic cylinder (2) is fixed in a position relative to the pump, and the movable guide vane adjustment mechanism is installed on the pump; the piston rod (21) is connected to the movable guide vane adjustment mechanism, and a movement of the piston rod (21) is configured to be transmitted to a movable guide vane through the movable guide vane adjustment mechanism, so as to realize an adjustment of an opening of the movable guide vane.
3. The flow self-adaptive guide vane adjustment apparatus based on the hydraulic transmission according to claim 1, further comprising a cam mechanism, wherein the cam mechanism comprises a cam (3), a follower (33), and a rack (34); the cam (3) is connected to the piston rod (21); the cam (3) is a form-closed moving cam and provided with a groove (31) thereon; the follower (33) is arranged in the rack (34), the rack (34) restricts a movement of the follower (33), so that the follower (33) is configured to reciprocate linearly in only one direction; a roller (32) is provided at an end of the follower (33), and the roller (32) is arranged in the groove (31) of the cam; a movement of the piston rod (21) drives the cam (3) to move, and causes the follower (33) to reciprocate linearly in the direction restricted by the rack (34).
4. The flow self-adaptive guide vane adjustment apparatus based on the hydraulic transmission according to claim 3, further comprising a pump and a movable guide vane adjustment mechanism, wherein the pump comprises an impeller (7), a pump body (5), and a shaft (8); the venturi tube (1) is installed at an outlet of the pump, the hydraulic cylinder (2) is fixed in a position relative to the pump, and the movable guide vane adjustment mechanism is installed on the pump; the follower (33) of the cam mechanism is connected to the movable guide vane adjustment mechanism, and the movement of the follower (33) is configured to be transmitted to a movable guide vane through the movable guide vane adjustment mechanism, so as to realize an adjustment of an opening of the movable guide vane. Lt
5. The flow self-adaptive guide vane adjustment apparatus based on the hydraulic transmission according to claim 2 or 4, wherein the movable guide vane is installed in front of an inlet of the impeller of the pump, and/or installed behind an outlet of the impeller of the pump.
6. The flow self-adaptive guide vane adjustment apparatus based on the hydraulic transmission according to claim 1, wherein the inlet section interface (15) comprises a pressure tap arranged on a wall surface of the inlet section (II), and the pressure tap is perpendicular to a flow direction to obtain a static pressure of the inlet section (11).
7. The flow self-adaptive guide vane adjustment apparatus based on the hydraulic transmission according to claim 1, wherein the inlet section interface (15) comprises a pressure tap extending into a center of the inlet section (11) through an elbow, and the pressure tap faces a direction of an incoming flow to obtain a total pressure of the inlet section (11).
8. The flow self-adaptive guide vane adjustment apparatus based on the hydraulic transmission according to claim 1 or 3, wherein one or more flow self-adaptive guide vane adjustment apparatuses based on hydraulic transmission are provided.