Reducing gate position adjusting mechanism of torsion type pipeline water turbine
By introducing a movable rectifier grid and a variable pitch spring design into the torsion pipe turbine, the adaptive position adjustment of the rectifier grid is achieved, which solves the problems of eddy vibration and water energy loss caused by flow velocity changes, and improves fluid stability and turbine efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- GUANGDONG UNIV OF TECH
- Filing Date
- 2025-05-26
- Publication Date
- 2026-05-01
AI Technical Summary
When the fluid velocity changes, the fixed position of the rectifier grid in the torsional pipe turbine causes vibration and noise from the eddy currents, and the eddy currents on the surface of the rectifier grid blades cause water energy loss. The existing design cannot adaptively adjust this.
The design employs a movable rectifier grid and a variable pitch spring. The adaptive position adjustment of the rectifier grid is achieved through guide slots and sliding slot modules. Combined with the NACA0020 airfoil blade, the drag adjustment is provided by the change in the stiffness coefficient of the variable pitch spring.
It effectively suppresses eddy current vibration, improves fluid stability, reduces head loss, increases turbine efficiency, and provides rectification effects to adapt to changes in flow velocity.
Smart Images
Figure CN224187684U_ABST
Abstract
Description
A torsion-type pipe turbine rectifier grid position adjustment mechanism Technical Field
[0001] This utility model relates to the technical field of turbine rectifier grids, and in particular to a torsion-type pipe turbine rectifier grid position adjustment mechanism. Background Technology
[0002] A flow rectifier can homogenize the fluid distribution in the flow field and suppress the generation of eddies in the surrounding flow field, thereby improving the fluid conditions in the fluid domain. Due to the asymmetric structure of the torsional impeller and the fluid restriction caused by the pipe wall in the working environment, torsional pipe turbines are more prone to generating eddies in the wake field compared to conventional turbines, and these eddies require a longer time to dissipate. Therefore, installing a flow rectifier in the wake field that can autonomously adjust its position according to the flow field conditions is of significant research value for improving the fluid conditions in the wake field, suppressing vibration and noise caused by eddies in the pipe, reducing head loss in the pipe, and improving turbine efficiency.
[0003] It should be noted that the rectification effect of the rectifier grid is related to the relative position of the rectifier grid and the vortex. When the fluid velocity changes or fluctuates within a certain range, the position of the vortex and the optimal position of the rectifier grid will also change. Existing rectifier grid structures are all installed in fixed positions, without considering that the fluid conditions in the flow domain will change when the fluid velocity changes. Therefore, the position where the rectifier grid can exert its optimal rectification effect may also change. The fluid velocity is lower and the flow field is more turbulent in the area from the vortex center to the impeller because it has just passed the impeller. Furthermore, this region is close to the impeller, and the vortices generated in this region can easily have an adverse effect on the impeller's operation, a phenomenon that is more pronounced for torsional impellers. Downstream of the vortex center, the vortex gradually dissipates, and the flow field tends to be stable. Therefore, placing the rectifier grid slightly upstream of the vortex center can better exert its rectification effect.
[0004] Secondly, the cross-sectional shape of the rectifier blades in existing studies is rectangular. While they perform rectification in the fluid, eddies are generated on the blade surface due to boundary layer separation, leading to water energy loss. Therefore, optimizing the shape of the rectifier blades to suppress this water energy loss and further improve energy utilization efficiency is an important research direction. Summary of the Invention
[0005] The purpose of this invention is to provide a torsion-type pipeline turbine rectifier grid position adjustment mechanism to meet the need for adaptive adjustment of the rectifier grid position.
[0006] To address the aforementioned technical problems, this utility model provides a torsion-type pipeline turbine rectifier grid position adjustment mechanism, comprising a conveying pipeline, a sliding groove module, and a movable rectifier grid. The conveying pipeline has a guide groove extending along the conveying direction of the pipeline. The sliding groove module is located outside the conveying pipeline, and its interior communicates with the guide groove. A variable pitch spring is located inside the sliding groove module, and its extension / retraction direction is consistent with the extension direction of the guide groove. The movable rectifier grid is slidably disposed within the conveying pipeline and includes a connecting rod and a sliding block. One end of the connecting rod passes through the guide groove and is connected to the sliding block. The sliding block is fixedly connected to one end of the variable pitch spring. When the movable rectifier grid is subjected to fluid scouring, the variable pitch spring provides resistance to the movable rectifier grid, causing it to move along the guide groove to a point of force equilibrium.
[0007] In one embodiment, the sliding groove module is provided with a guide rod, the extension direction of the guide rod is consistent with the extension direction of the guide groove, and the variable pitch spring is sleeved on the guide rod.
[0008] In one embodiment, the sliding block has a through hole through which one end of the guide rod passes, and the variable pitch spring is compressed between the sliding block and the other end of the guide rod.
[0009] In one embodiment, one end of the guide rod extends through the sliding block to the outside of the sliding groove module and is connected to a preload adjustment knob; the other end of the guide rod is threadedly connected to a preload adjustment block, a portion of which is slidably installed in the guide groove to form a limiting guide assembly structure between the preload adjustment block and the guide groove; the variable pitch spring is compressed between the sliding block and the preload adjustment block.
[0010] In one embodiment, the pitch at both ends of the variable pitch spring is smaller than the pitch at its middle portion.
[0011] In one embodiment, the movable rectifier grid includes multiple rectifier blades, the airfoil of which is NACA0020.
[0012] In one embodiment, the connecting rod is connected between the end of the rectifier blade and the sliding block.
[0013] The beneficial effects of this utility model are as follows:
[0014] 1. The NACA0020 airfoil profile, which has better fluid performance, is used instead of the conventional rectangular blade profile to improve the fluid performance of the movable rectifier grid itself.
[0015] 2. The movable rectifier grid is set according to the position of the eddy, which provides a basis for the setting position of the movable rectifier grid. It is found that under this design, the optimal setting position of the movable rectifier grid is slightly upstream of the eddy center.
[0016] 3. Based on the changing pattern of vortex position when the flow velocity in the conveying pipeline changes, a scheme is designed to allow the movable rectifier grid to move downstream of the impeller when the flow velocity increases and move closer to the impeller when the flow rate decreases.
[0017] 4. A variable pitch spring is used to adjust the movable rectifier grid. Due to the characteristic that the spring constant of the variable pitch spring increases with the increase of compression, the movable rectifier grid can be adjusted normally under the condition of small flow velocity changes. Under the condition of large fluctuations, the spring force can be increased to ensure that the movable rectifier grid is located slightly upstream of the vortex center, while suppressing the vibration of the movable rectifier grid in the fluid and improving stability. Attached Figure Description
[0018] To more clearly illustrate the technical solution of this utility model, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0019] Figure 1 is a structural schematic diagram provided in an embodiment of the present utility model;
[0020] Figure 2 is a cross-sectional view of the structure shown in Figure 1;
[0021] Figure 3 is a schematic diagram of the application scenario of Figure 1;
[0022] Figure 4 is a schematic diagram of the movable rectifier grid structure in Figure 1.
[0023] The attached figures are labeled as follows:
[0024] 10. Conveying pipeline; 11. Guide channel;
[0025] 20. Sliding groove module; 21. Variable pitch spring; 22. Guide rod; 23. Slider; 24. Preload adjustment knob; 25. Preload adjustment block;
[0026] 30. Movable rectifier grid; 31. Connecting rod; 32. Sliding block; 321. Perforation; 33. Rectifier blade;
[0027] 40. Impeller. Detailed Implementation
[0028] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention.
[0029] Fluid analysis of a water turbine reveals a correlation between the fluid velocity and vortex distribution in its wake field: the velocity is lower from the vortex center to the impeller, while downstream of the vortex center, the vortex gradually stabilizes and its velocity gradually increases. Analysis of the drag force experienced by an object in a fluid shows that the drag is proportional to the square of the fluid velocity; therefore, the drag experienced by an object upstream of a vortex is less than that downstream.
[0030] The torsion-type inline turbine rectifier position adjustment mechanism designed in this paper is shown in Figure 1. It mainly consists of three parts: a movable rectifier 30, a sliding groove module 20, and a conveying pipe 10. To avoid excessive influence on the flow of fluid within the conveying pipe 10, the sliding groove module 20 is installed on the outer wall of the conveying pipe 10. The position of the movable rectifier 30 is fixed by the wall of the conveying pipe 10 and the sliding groove module 20, limiting its sliding within a certain range. A spring is installed within the sliding groove module 20 to provide thrust to the movable rectifier 30, so as to achieve the purpose of adaptive position adjustment of the movable rectifier 30 according to the fluid conditions.
[0031] Based on the force analysis of the movable rectifier grid 30, it can be concluded that for the movable rectifier grid 30 to reach a state of equilibrium at a certain position in the conveying pipe 10, the spring force F needs to be adjusted. s Equal to the resistance F experienced by the movable rectifier 30 in the water flow l That is, it satisfies equation (1). In actual working conditions, the water flow density ρ and the projected area S of the movable rectifier grid 30 in equation (2) are... r and drag coefficient C r All of these have been determined, therefore the resistance F experienced by the movable rectifier 30 in the water flow is... l The force is determined by the water flow velocity v. Considering the force change characteristics of the movable rectifier 30 before and after the vortex, the spring used in this study is a variable pitch spring 21, which has the characteristic that the spring constant increases with the increase of the force. From equation (3), it can be seen that during the compression process, the spring constant k and the deformation Δx of the variable pitch spring 21 increase simultaneously. When the variable pitch spring 21 is compressed beyond a certain position, the elastic force generated by the variable pitch spring 21 will increase sharply.
[0032] Therefore, the design principle of the regulating mechanism is: when the water flow velocity v changes within a small range, F lAs the equation changes, the two sides of the equality in equation (1) are no longer equal. At this point, in order to achieve a new equilibrium, the spring constant k changes less, and the change is mainly due to the change in the spring deformation Δx, which in turn drives the movable rectifier grid 30 to move, causing the elastic force F generated by the variable pitch spring 21 to change. s Reconnect with water flow resistance F l When the flow velocity v fluctuates significantly, causing the movable rectifier 30 to tend to move downstream of the vortex center, the spring constant k of the variable pitch spring 21 also increases due to its characteristics. At this time, the elastic force F generated by the variable pitch spring 21... s It will rise sharply, thus preventing the movable rectifier grid 30 from moving further downstream and keeping it in the middle and upper reaches of the vortex.
[0033] F1 = F s (1)
[0034]
[0035] F s =kΔx(3)
[0036] In the formula: F l N; F represents the resistance experienced by the movable rectifier grid 30 in the water flow. s ρ is the elastic force exerted by the variable pitch spring 21 on the movable rectifier grid 30, in N; ρ is the water flow density, in kg / m³. 3 v is the water flow velocity, m / s; S r The projected area of the movable rectifier 30 perpendicular to the direction of water flow velocity is m. 2 C r Δx is the drag coefficient of the movable rectifier grid 30 in water; k is the stiffness coefficient of the variable pitch spring 21, N / m; Δx is the deformation of the variable pitch spring 21, m.
[0037] Specifically, an embodiment of the above-mentioned torsion-type pipe turbine rectifier grid position adjustment mechanism is shown in Figures 1 to 4, including a conveying pipe 10, a sliding groove module 20, and a movable rectifier grid 30; a guide groove 11 is provided on the conveying pipe 10, extending along the conveying direction of the conveying pipe 10; the sliding groove module 20 is located outside the conveying pipe 10, and its interior is connected to the guide groove 11; a variable pitch spring 21 is provided inside the sliding groove module 20, and the extension / retraction direction of the variable pitch spring 21 is... The movable rectifier 30 is slidably disposed within the conveying pipe 10, and is provided with a connecting rod 31 and a sliding block 32. One end of the connecting rod 31 passes through the guide groove 11 and is connected to the sliding block 32. The sliding block 32 is fixedly connected to one end of the variable pitch spring 21. When the movable rectifier 30 is flushed by fluid, the variable pitch spring 21 provides resistance to the movable rectifier 30 so that the movable rectifier 30 moves along the guide groove 11 to the point of force equilibrium.
[0038] As shown in Figures 1 and 2, in this embodiment, a guide rod 22 is provided inside the sliding groove module 20. The extension direction of the guide rod 22 is consistent with the extension direction of the guide through groove 11. A variable pitch spring 21 is sleeved on the outside of the guide rod 22.
[0039] With this configuration, the guide rod 22 will fix the installation position of the variable pitch spring 21, ensuring that the variable pitch spring 21 can only extend and retract along the axial direction of the guide rod 22.
[0040] As shown in Figures 3 and 4, in this embodiment, the sliding block 32 is provided with a through hole 321 for one end of the guide rod 22 to pass through, and a variable pitch spring 21 is compressed between the other end of the sliding block 32 and the guide rod 22.
[0041] With this configuration, once the variable pitch spring 21 undergoes extension and contraction, it will generate a corresponding force that acts on the sliding block 32, thereby driving the sliding block 32 to move back and forth on the guide rod 22. Therefore, once the sliding block 32 moves, the synchronous movement of the sliding block 32 and the movable rectifier grid 30 is achieved.
[0042] Furthermore, the sliding block 32 is also connected to the slider 23, which is used for the radial positioning of the movable rectifier grid 30.
[0043] As shown in Figures 1 to 3, in this embodiment, one end of the guide rod 22 extends through the sliding block 32 to the outside of the sliding groove module 20 and is connected to the preload adjustment knob 24; the other end of the guide rod 22 is threadedly connected to the preload adjustment block 25, and a part of the preload adjustment block 25 is slidably installed in the guide groove 11 so that a limiting guide assembly structure is formed between the preload adjustment block 25 and the guide groove 11; the variable pitch spring 21 is compressed between the sliding block 32 and the preload adjustment block 25.
[0044] With this setup, once the guide rod 22 is rotated using the preload adjustment knob 24, the guide rod 22 and the preload adjustment block 25 essentially form a screw drive, enabling linear reciprocating movement control of the preload adjustment block 25. This allows for adjustment of the initial compression of the variable pitch spring 21 to meet application requirements under different conditions.
[0045] As shown in Figure 2, in this embodiment, the pitch at both ends of the variable pitch spring 21 is smaller than the pitch in the middle.
[0046] As shown in Figure 4, this embodiment features a movable rectifier grid 30 comprising multiple rectifier blades 33, with the airfoil of the rectifier blades 33 being the NACA0020 airfoil.
[0047] With this configuration, the NACA0020 airfoil can be used to suppress the generation of wall vortices on the movable rectifier grid 30.
[0048] As shown in Figure 4, in this embodiment, the connecting rod 31 is connected between the end of the rectifier blade 33 and the sliding block 32.
[0049] When the above embodiments are applied, as shown in Figures 1 to 4, the specific working principle is as follows:
[0050] When water usage is low and the flow rate in the delivery pipeline 10 is small, a movable rectifier grid 30 and a sliding groove module 20 are installed on the delivery pipeline 10. The preload adjustment knob 24 is adjusted according to the flow velocity in the delivery pipeline 10. This knob rotates the guide rod 22, causing the preload adjustment block 25, which is threadedly connected to the guide rod 22, to move along the guide rod 22. Simultaneously, the change in the position of the preload adjustment block 25 compresses or stretches the variable pitch spring 21. The deformation of the variable pitch spring 21 applies a spring force to the movable rectifier grid 30. Simultaneously, the movable rectifier grid 30 experiences fluid resistance within the delivery pipeline 10. The movable rectifier grid 30 reaches equilibrium under the combined action of the resistance and the spring force. The equilibrium position during the low water usage period is taken as the initial position of the movable rectifier grid 30. When water demand increases and the water flow velocity increases, the intensity of the vortex generated downstream of the impeller 40 increases, and the vortex center moves downstream of the impeller 40. As the water flow velocity increases, the resistance experienced by the movable rectifier grid 30 also increases, causing it to move downstream of the impeller 40 and compress the variable pitch spring. Consequently, the elastic force generated by the variable pitch spring 21 also increases. Once the elastic force generated by the variable pitch spring 21 equals the water flow resistance again, the movable rectifier grid 30 moves to a new equilibrium position. Simultaneously, if the flow velocity fluctuates significantly, causing the movable rectifier grid 30 to tend to move downstream of the vortex center, the stiffness coefficient of the variable pitch spring 21 also increases due to its characteristics. At this time, the elastic force generated by the variable pitch spring 21 rises sharply, thus preventing the movable rectifier grid 30 from moving further downstream and maintaining it in the upper-middle position of the vortex. This adjustment method can adapt to load changes under different flow velocities, effectively suppressing vibration and improving stability. It keeps the movable rectifier grid 30 in a position near the vortex center, slightly upstream, and automatically adjusts according to changes in flow velocity within a certain range, thereby achieving the best rectification effect.
[0051] The above description is the preferred embodiment of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this utility model, and these improvements and modifications are also considered to be within the protection scope of this utility model.
Claims
1. A torsion-type pipe turbine rectifier grid position adjustment mechanism, characterized in that, The system includes a conveying pipe, a sliding groove module, and a movable rectifier grid. The conveying pipe has a guide groove extending along its conveying direction. The sliding groove module is located outside the conveying pipe, and its interior communicates with the guide groove. A variable pitch spring is installed inside the sliding groove module, with its extension / retraction direction aligned with the extension direction of the guide groove. The movable rectifier grid is slidably disposed within the conveying pipe and includes a connecting rod and a sliding block. One end of the connecting rod passes through the guide groove and is connected to the sliding block. The sliding block is fixedly connected to one end of the variable pitch spring. When the movable rectifier grid is subjected to fluid scouring, the variable pitch spring provides resistance to the grid, allowing it to move along the guide groove to a point of force equilibrium.
2. The torsion-type pipeline turbine rectifier grid position adjustment mechanism according to claim 1, characterized in that, The sliding groove module is equipped with a guide rod, the extension direction of which is consistent with the extension direction of the guide groove, and the variable pitch spring is sleeved on the outside of the guide rod.
3. The torsion-type pipe turbine rectifier grid position adjustment mechanism according to claim 2, characterized in that, The sliding block has a through hole through which one end of the guide rod passes, and the variable pitch spring is compressed between the sliding block and the other end of the guide rod.
4. The torsion-type pipeline turbine rectifier grid position adjustment mechanism according to claim 3, characterized in that, One end of the guide rod passes through the sliding block and extends to the outside of the sliding groove module, and is connected to a preload adjustment knob; the other end of the guide rod is threadedly connected to a preload adjustment block, a portion of which is slidably installed in the guide groove to form a limiting guide assembly structure between the preload adjustment block and the guide groove; the variable pitch spring is compressed between the sliding block and the preload adjustment block.
5. The torsion-type pipe turbine rectifier grid position adjustment mechanism according to claim 1, characterized in that, The pitch at both ends of the variable pitch spring is smaller than the pitch in its middle.
6. The torsion-type pipeline turbine rectifier grid position adjustment mechanism according to claim 1, characterized in that, The movable rectifier grid includes multiple rectifier blades, and the airfoil of the rectifier blades is NACA0020 airfoil.
7. The torsion-type pipe turbine rectifier grid position adjustment mechanism according to claim 6, characterized in that, The connecting rod is connected between the end of the rectifier blade and the sliding block.