Energy dissipation and flow stabilization device applied to curve type stilling pool

Abstract

The invention relates to the technical field of stilling pools, in particular to an energy dissipation and flow stabilization device applied to a curve type stilling pool. The device comprises an inlet straight section, a bend section is fixedly connected to the end of the inlet straight section and used for guiding water flow to turn and forming a preset flow state, an outlet adjusting section is fixedly connected to the downstream end of the bend section, a plurality of T-shaped piers are arranged in the outlet adjusting section at intervals, and the T-shaped piers are arranged in the water flow direction. The flow state correcting device is used for correcting the flow state of water flow generating bias flow after bending of the bend section. Water flow enters the concave bank through the inlet straight section, then is guided to the outlet adjusting section through the curve section and the convex bank and finally is divided by the T-shaped piers for energy dissipation, the curve type stilling pool is matched with the T-shaped piers, the front edge structure can divide the concentrated water flow of the concave bank into a plurality of secondary flows, the turbulent shear area is greatly increased, the water flow energy dissipation rate is increased by 60%, and the energy dissipation rate is increased by 60%. And the flushing risk of a downstream riverbed is effectively reduced.

Description

Technical Field

[0001] This invention relates to the field of stilling basin technology, and more specifically, to an energy dissipation and flow stabilization device applied to a curved stilling basin. Background Technology

[0002] In the field of water conservancy engineering, the water flow in a curved stilling basin is complex under the coupling effect of centrifugal force and inertial force in the bend. It has problems such as concentrated flow velocity on the concave bank and large horizontal gradient of the water surface, which leads to the occurrence of deflecting flow downstream, which intensifies the scouring of the riverbed and bank slope and affects the safety and stability of the project.

[0003] Studies have shown that T-shaped piers can enhance water flow turbulence and improve energy dissipation efficiency. Currently, energy dissipators on the market are mainly divided into single energy dissipators and composite energy dissipators.

[0004] Each type of energy dissipator has its own shortcomings. Bottom flow energy dissipators involve large engineering volume and high cost, and their energy dissipation efficiency depends on the length of the pool. Flow dissipators suffer from severe atomization and are susceptible to cavitation and wear. Surface flow energy dissipators depend on the downstream water depth and have limited applicability. Stepped energy dissipators have high geological requirements, are difficult to construct, and have high costs. Composite energy dissipators have complex designs, require precise calculation of flow coupling, have high construction and maintenance costs, and require extremely high construction precision. In contrast, T-shaped piers have a simple structure, standardized design, low construction risk, low complexity, significant economic benefits, better cost control, and a wide range of applications.

[0005] However, current research on T-shaped piers is mostly focused on rectangular T-shaped piers, and the research on their hydraulic characteristics under curved boundary conditions is not in-depth enough. As a result, it is difficult to give full play to the energy dissipation advantages of T-shaped piers. Consequently, the flow velocity concentration on the concave bank of the curved stilling basin leads to a significant horizontal drop in the water surface and poor adaptability to curved flow channels. In view of this, we propose an energy dissipation and flow stabilization device for curved stilling basins. Summary of the Invention

[0006] The purpose of this invention is to provide an energy dissipation and flow stabilization device for use in curved stilling basins, so as to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides an energy dissipation and flow stabilization device for use in a curved stilling basin, comprising an inlet straight section, wherein a curved section is fixedly connected to the end of the inlet straight section for guiding the water flow to change direction and forming a preset flow pattern;

[0008] The downstream end of the bend is fixedly connected to an outlet adjustment section, and multiple T-shaped piers are spaced apart in the outlet adjustment section. The T-shaped piers are arranged along the water flow direction and are used to correct the flow pattern of the water flow that deviates after the bend of the bend.

[0009] Meanwhile, the T-shaped pier divides the concentrated water flow into multiple secondary water flows through its geometric shape, promotes the turbulent energy dissipation of the water flow in the outlet adjustment section, avoids the direct impact of the concentrated water flow on the downstream structure, and realizes the synergistic effect of energy dissipation and flow state optimization.

[0010] The outlet adjustment section can adaptively adjust the position of the water flow guided through the curved section, and the T-shaped pier adapts to the boundary shape of the curved section, avoiding the adaptability problem caused by the fixed shape and curved water flow. The T-shaped pier can enhance collision and mixing by dividing the concentrated water flow into multiple secondary water flows, improve the turbulent energy dissipation efficiency, and effectively avoid local turbulent dead angles and backflow.

[0011] As a further improvement of the technical solution, the curved section includes a concave bank, a convex bank, and a curved section, wherein the end of the inlet straight section is fixedly connected with the concave bank, the other end of the concave bank is smoothly connected with one end of the convex bank through the curved section, forming a curved water flow channel adapting to the rugged terrain, and the curved section adopts a smooth curve shape, and the curvature radius is determined according to the terrain condition, water flow speed, and turning angle of the stilling basin;

[0012] The combination of the concave bank, the convex bank, and the curved section forms a curved water flow channel adapting to the rugged terrain, the inlet straight section is fixedly connected with the concave bank to ensure the smoothness of the water flow entering, the curved section adopts a smooth curve shape, and the curvature radius is determined according to the terrain condition, water flow speed, and turning angle, which can better adapt to the natural deviation trend of the water flow caused by the centrifugal force, make the water flow smoothly turn along the tangent direction of the curve, avoid water flow separation, impact, or turbulent intensification caused by sharp turns, and reduce the water flow aggregation intensity on the concave bank side and the local scouring risk.

[0013] As a further improvement of the technical solution, the outlet adjustment section is arranged at the downstream end of the curved section, one end of the outlet adjustment section is fixedly connected with the highest end of the convex bank to ensure that the outlet adjustment section and the convex bank form a straight water flow channel, and the outlet adjustment section adopts a gradually widened micro-curved structure, the cross-sectional profile of which is adapted to the end of the convex bank and smoothly transitions along the water flow direction;

[0014] The gradually widened micro-curved structure adopted by the outlet adjustment section has a cross-sectional profile adapted to the end of the convex bank and smoothly transitions along the water flow direction, which can make the water flow flow smoothly without any obstruction and preliminarily reduce the flow speed through the gradually increasing water cross section.

[0015] As a further improvement of the technical solution, a plurality of T-shaped piers are arranged, and each T-shaped pier is arranged in sequence along the water flow direction of the outlet adjustment section, the T-shaped pier is made of glass fiber composite material or carbon fiber composite material, the T-shaped pier has a whole "T" shape structure, and is arranged at the end of the outlet adjustment section;

[0016] A plurality of T-shaped piers are arranged in sequence along the water flow direction of the outlet adjustment section, and can uniformly act on the water flow.

[0017] As a further improvement of the technical solution, a plurality of detection points are arranged on the surfaces of the inlet straight section, the curved section and the outlet adjustment section, and the shape and size of the T-shaped pier can be adaptively adjusted according to the terrain conditions and water flow characteristics in the actual application scene.

[0018] Compared with the prior art, the application has the following beneficial effects:

[0019] 1. In the energy dissipation and flow stabilizing device applied to the curved-type stilling basin, water flows into the concave bank through the inlet straight section, is guided to the outlet adjustment section through the curved section and the convex bank, and is finally divided and dissipated by the T-shaped pier. The design of the curved-type stilling basin combined with the T-shaped pier can divide the concentrated water flow on the concave bank into a plurality of secondary flows by the front edge structure, greatly increase the turbulent shear area, and increase the water flow energy dissipation rate by 60%, thereby effectively reducing the scouring risk of the downstream riverbed.

[0020] Secondly, the structural stability is enhanced. The T-shaped pier adopts a “T” shaped structure combined with the contour design of the curved section, disperses the problem of concentrated hydraulic load, reduces the maximum stress of the pier body by 15%-25%, reduces the probability of cavitation damage, prolongs the service life of the overall structure, the curved section guides the water flow to smoothly turn, the micro-curved structure of the outlet adjustment section gradually expands and adapts to the water flow form, the T-shaped pier can correct the deflected flow, compared with the traditional design, the uniformity of the transverse flow velocity distribution in the stilling basin is improved by 30%, and the formation of local backflow and vortex is avoided, and the T-shaped pier can adapt to different flow velocities and water depths.

[0021] 2. In the energy dissipation and flow stabilizing device applied to the curved-type stilling basin, by optimizing the shape, size of the T-shaped pier and the structural parameters of the curved section and the outlet adjustment section, the amount of concrete and other materials is reduced by 10% under the premise of ensuring the same energy dissipation effect, thereby directly reducing the construction cost. At the same time, due to the more reasonable structure design of the curved-type stilling basin and the T-shaped pier, the anti-cavitation performance is improved, and the maintenance period is prolonged from 2-3 years of the traditional design to about 5 years. DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall T-shaped pier of the application;

[0023] Figure 2 It is a schematic diagram of the T-shaped pier of the application;

[0024] Figure 3 It is a schematic diagram of the T-shaped pier view of the application;

[0025] Figure 4 It is a schematic diagram of the cross-section pile number distribution of the application;

[0026] Figure 5The schematic diagram of the test device of the present application;

[0027] Figure 6 The layout of the T-shaped pier of the optimal scheme of the present application;

[0028] Figure 7 The flow pattern of the optimal scheme of the present application;

[0029] Figure 8 The cross-section water depth diagram of the first optimal scheme of the present application;

[0030] Figure 9 The cross-section water depth diagram of the second optimal scheme of the present application;

[0031] Figure 10 The mean main effect diagram of the present application;

[0032] Figure 11 The change schematic diagram of the T-shaped pier layout from the non-energy dissipating work to the stilling basin physical model of the present application;

[0033] The meanings of the respective labels in the diagram are as follows:

[0034] 100, the inlet straight section;

[0035] 200, the curved section;

[0036] 300, the outlet adjustment section;

[0037] 400, the T-shaped pier; 401, the front pier; 402, the leg. DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative work are within the protection scope of the present application.

[0039] In order to overcome the problems that the current curve-type stilling basin is affected by the centrifugal force and the inertial force of the curved section together, most of the water flow is concentrated and gathered on the concave bank, the water depth on the concave bank is often higher than that on the convex bank, the water surface transverse slope is formed, the cross-section flow velocity distribution is uneven, and the adverse hydraulic phenomena such as water surface super-high, downstream deflected flow and the like occur, which is not conducive to the long-term safe and stable operation of the stilling basin. Please refer to Figures 1-11As shown, the embodiment provides an energy dissipation and flow stabilizing device applied to a curve-type stilling basin, which comprises an inlet straight section 100, the end of which is fixedly connected with a curved section 200 for guiding water flow diversion and forming a preset flow state; the downstream end of the curved section 200 is fixedly connected with an outlet adjusting section 300, the curved section 200 at both ends of which connected smoothly with the inlet straight section 100 and the outlet adjusting section 300 forms a curve-type stilling basin adapted to rugged terrain, and the curved section 200 adopts a smooth curve shape, the curvature radius of which is determined according to the terrain condition of the area where the stilling basin is located, the water flow velocity and the diversion angle;

[0040] The outlet adjusting section 300 adopts a gradually widened micro-curve structure and keeps a smooth transition form along the water flow direction;

[0041] A plurality of T-shaped piers 400 are arranged in the outlet adjusting section 300, the T-shaped piers 400 are arranged in sequence along the water flow direction of the outlet adjusting section 300, the T-shaped pier 400 is composed of a front pier 401 and a leg 402, and one end of the leg 402 is connected with the front pier 401 in a T shape;

[0042] It is worth mentioning that the measuring device and the layout form simulation library are also included, the layout form simulation library is used to simulate the linear relationship between the water flow data stored after training and the layout form of the T-shaped pier 400, the measuring device is used to measure the water flow data under the current working condition, input the layout form simulation library and output the layout form of the T-shaped pier 400, so that the T-shaped pier 400 is laid out on the outlet adjusting section 300 according to the layout form, used to correct the flow state of the water flow deflected after bending in the curved section 200, and divide the concentrated water flow into a plurality of secondary water flows.

[0043] Specifically, the measuring device comprises a water depth measuring instrument, a flow velocity measuring instrument and a flow measuring instrument, and the following postures are included when measuring:

[0044] Posture one, water depth measurement:

[0045] A plurality of water depth measurement sections are arranged along the curved section 200 of the stilling basin, the more the sections, the better, a plurality of measuring points are arranged from the concave bank to the convex bank of each section, the more the measuring points, the better, under the premise of ensuring high precision, accurate water depth measuring instruments such as water level measuring needles, steel rulers and levels are used to measure the water depth of each section and each measuring point, due to the influence of the wall adhesion force and the water flow characteristics, the water depth and other parameters of the two banks are often different from the center of the flow channel, considering the comprehensiveness of the test determination parameters, 3 measuring points are arranged for each measuring section, i.e. the left bank, the center and the right bank, and the measuring points near the concave bank and the convex bank should be kept a certain distance from the slot wall;

[0046] Posture two, flow velocity measurement

[0047] Similar to the water depth section, multiple velocity measurement sections should be arranged along the 200-meter bend of the spillway structure. Multiple measuring points should be arranged from the concave bank to the convex bank of each section. A Pitot tube, a precise velocity measuring instrument, should be used to measure the velocity of different water layers such as the upper, middle and lower layers of each section and measuring point.

[0048] Attitude 3, Flow Measurement

[0049] High-precision flow measurement instruments are used to measure and monitor the discharge flow of spillway structures. It is essential to ensure that the inlet and outlet flow rates remain balanced. The flow measurement instrument is a rectangular thin-walled weir. The calculation formula is shown in Formula 1-2.

[0050]

[0051]

[0052] In the formula, Q is the outflow rate, m 3 / s; m0 is the flow coefficient of the rectangular thin-walled weir, dimensionless; b is the width of the weir crest, m; g is the acceleration due to gravity, taken as 9.81 m / s²; H is the head at the weir crest, m; B is the width of the upstream diversion channel, m; P is the height of the rectangular thin-walled weir, m;

[0053] Seven geometric parameters affecting the hydraulic characteristics of the T-shaped pier 400 were selected: pier thickness (A), abutment thickness (B), pier height (C), pier width (D), tail sill height (E), outrigger length (F), and pier spacing (G). Reasonable horizontal values ​​were set for each parameter, and multiple sets of tests were conducted under different flow conditions to optimize the layout of the T-shaped pier 400. Fourteen measurement sections were arranged along the stilling basin; the specific section station distribution is shown below. Figure 4 And Table 1:

[0054] Table 1. Distribution of station numbers of the measured cross-sections of the combined stilling basin in the optimal scheme.

[0055] .

[0056] The layout simulation library includes a curved stilling basin under different working conditions by changing the water flow conditions, including flow rate and water level.

[0057] The water depth, velocity, and pressure data of the curved stilling basin under different working conditions were measured using measuring equipment. Based on the evaluation indicators of water flow pattern, average outlet velocity, water depth and velocity in typical cross-sections, the arrangement of the T-shaped piers was determined.

[0058] Compared with existing technologies related to curved channel bends, curved stilling basins, and T-shaped piers, the curved stilling basin T-shaped pier has the following advantages and positive effects:

[0059] 1. Technical advantages

[0060] (1) Energy dissipation efficiency is significantly improved:

[0061] Through the design of the curved-type stilling basin T-pier 400, the acute-angle structure of the front edge divides the concave bank concentrated flow into multiple secondary flows, increasing the turbulent shear area and improving the energy dissipation rate by 60%, effectively reducing the risk of downstream riverbed erosion.

[0062] (2) Structural stability is enhanced:

[0063] The composite design of T-shaped cross-section and curved profile disperses the hydraulic load concentration problem, reduces the maximum stress of the pier body by 15-25%, reduces the probability of cavitation damage, and prolongs the service life.

[0064] (3) Better flow field adaptability:

[0065] The curved-type stilling basin T-pier 400 can adapt to different flow velocities and water depths, and compared to traditional designs, the uniformity of transverse flow velocity distribution in the stilling basin is improved by 30%, avoiding the formation of local backflow and vortex.

[0066] 2. Economic advantages

[0067] (4) Reduced material cost and maintenance cost:

[0068] By optimizing the curve parameters of the pier body, the amount of concrete is reduced by 10% under the same energy dissipation effect, reducing construction costs, and the anti-cavitation performance of the curved-type stilling basin T-pier is improved, with a maintenance cycle extended from 2-3 years in traditional designs to about 5 years, reducing the frequency of shutdown maintenance and operation and maintenance costs.

[0069] 3. Application advantages

[0070] (5) Expanded application scope and ecological friendliness:

[0071] It is suitable for high water head and large flow discharge scenarios (such as reservoirs and hydropower stations), and can adapt to narrow or asymmetric terrain, breaking through the limitations of traditional stilling basin piers under terrain conditions.

[0072] (optimized water flow pattern reduces downstream riverbed disturbance and reduces negative impacts on aquatic ecological environment, meeting the requirements of green water conservancy projects.

[0073] Summary: The invention makes significant progress in energy dissipation efficiency, structural durability, economy, and environmental adaptability through the innovative design of the curved-type T-pier, especially suitable for water conservancy projects under complex hydrological conditions. Its technical solution effectively solves the problems of high energy consumption, easy damage, and high cost of traditional stilling basins, providing an efficient, reliable, and sustainable solution for flood discharge and energy dissipation facilities, with broad engineering application prospects.

[0074] Example 1:

[0075] In order to train the arrangement form simulation library, the linear relationship between the stored water flow data after simulation training and the T-shaped pier 400 arrangement form is realized, and the specific steps are as follows:

[0076] The test device is mainly composed of a water circulation system and a water inlet building (see Figure 5 ), and the water circulation system is composed of a water storage tank, a downstream river channel simulation area, a water measuring weir, an underground reservoir and a water diversion pipe. The water discharge building is composed of a control section and a stilling basin. The device is composed of a continuous bend section and an outlet adjustment section, the slope along the path is i=0.001, the total length of the flow process is S=107.96m, the width of the inlet flow channel is 37.53m, and the width of the outlet flow channel is 50.48m;

[0077] Combined with Figure 3 The overall shape is in the form of a letter T, and a orthogonal test scheme is designed:

[0078] Seven geometric parameters (front pier thickness A, branch pier thickness B, pier height C, front pier width D, tail sill height E, branch leg length F, and pier spacing G) that affect the hydraulic characteristics of the T-shaped pier flow diversion and energy dissipation in the curved stilling basin are comprehensively selected. The front pier thickness A refers to the horizontal projection distance between the water-facing surface and the backwater surface, which can also be understood as the width of the pier. The branch pier thickness B refers to the horizontal projection thickness of the T-shaped branch pier (lateral support section) perpendicular to the water flow direction. The pier height C refers to the vertical height of the T-shaped pier from the base to the top, including the overall height of the front pier and the branch pier. The front pier width D refers to the horizontal projection length of the front pier along the center line of the flow channel (perpendicular to the water flow direction). The tail sill height E refers to the vertical height of the tail sill at the end of the stilling basin (relative to the pool bottom). The branch leg length F refers to the horizontal projection length of the branch pier extending laterally from the front pier end (parallel to the water flow direction). The pier spacing G refers to the distance between adjacent two T-shaped piers along the center line of the flow channel. According to the above variable factors, a 7-factor 2-level orthogonal test table is designed, and the 7 factors are front pier thickness, branch pier thickness, pier height, front pier width, tail sill height, branch leg length, and pier spacing. The orthogonal test table is as follows (Table 2):

[0079] Table 2 12 test schemes

[0080]

[0081] Through numerical simulation calculation method, the specific arrangement parameters of T-shaped pier are changed, the front pier thickness, branch pier thickness, pier height, front pier width, tail sill height, branch leg length, and pier spacing are changed, 12 different T-shaped pier arrangement schemes are designed, and the evaluation indexes of flow pattern, outlet average flow velocity, typical cross section water depth and flow velocity are determined to determine the optimal arrangement form of T-shaped pier.

[0082] As Figures 6-9The optimal scheme T-shaped pier layout and the optimal scheme flow pattern, and the optimal scheme cross-section water depth chart can be obtained by simulation, it can be seen that the water depth of convex bank is still larger than that of concave bank and the flow line distribution of convex bank is more stable than that of concave bank, thus it can be concluded that the flow pattern and flow line after adding T-shaped pier are greatly improved compared with the original scheme, and finally the flow velocity of the optimal scheme import cross-section is 3.16 m / s, which is reduced by 31.35% compared with the original scheme.

[0083] Secondly, orthogonal test data analysis:

[0084] (1) Analysis of variance: the factor with P value below 0.05 in the analysis of variance table is a significant factor, indicating that it has a significant influence on the optimization results in this optimization test. The analysis of variance results of this scheme are shown in Table 3.

[0085] Table 3 Analysis of variance table

[0086]

[0087] Through analysis of Table 3, it is known that the P value of pier height is 0.003, which indicates that it has a very significant influence on the optimization results; the influence of pier spacing is only second to that of pier height and front pier width, so the significant factors in this optimization test are the two significant influence factors of pier height and front pier width.

[0088] (2) Range analysis: front pier thickness A (m), support pier thickness B (m), pier height C (m), front pier width D (m), tail sill height E (m), leg length F (m), and pier spacing G (m), the mean response analysis table is shown in Table 4.

[0089] Table 4 Mean response analysis table

[0090]

[0091] Through analysis of the mean response table, the importance of factors is in the order of pier height, front pier width, pier spacing, tail sill height, support pier thickness, front pier thickness, and leg length. This is highly consistent with the significant factor ordering in the analysis of variance, indicating that the range analysis and the analysis of variance are reliable.

[0092] (3) Main effect analysis

[0093] Front pier thickness A (m), support pier thickness B (m), pier height C (m), front pier width D (m), tail sill height E (m), leg length F (m), and pier spacing G (m), Figure 10 The mean main effect diagram is as follows: the effect of each level can be judged according to the height of the points in each diagram, so as to obtain the specific parameters of the better arrangement type;

[0094] Through analysis of the mean main effect Figure 10, according to the height of the points of each figure to determine the role of each level of the situation. Analysis can get the optimal arrangement of the specific parameters for: the front pier thickness 0.7m, thick 1.2m, pier height 0.6m, the front pier width of 2m, tail high 3m, 4m long T-shaped pier legs, the evaluation index is the outlet flow velocity and the smaller the better.

[0095] Based on the above twelve groups of optimal scheme arrangement, based on model test, combined with the related literature set 12 groups of optimization scheme, through numerical simulation of each optimization scheme data. Tecpolt software analysis of the flow elements of the dangerous section and calculate the evaluation index outlet flow velocity, through the analysis of variance to get the significant factor for pier height and front pier width. Through range analysis obtained factor importance ranking in turn for pier height, front pier width, pier spacing, tail high, thick pier, front pier thickness, leg length. By main effect analysis to get the optimal arrangement of the specific parameters for: the front pier thickness 0.7m, thick 1.2m, pier height 0.6m, the front pier width of 2m, tail high 3m, 4m long T-shaped pier legs, for the optimal arrangement of the type of hydraulic characteristics numerical simulation research provides the basis.

[0096] Among them, the energy dissipater and energy dissipater arrangement scheme along the water depth distribution measurement as follows:

[0097] As Figure 11 (arrow shows no energy dissipater physical to the energy dissipater pool arrangement T-shaped pier physical map changes), according to the test to get the optimal arrangement of T-shaped pier design conditions, no energy dissipater and energy dissipater pool arrangement T-shaped pier, modification of the body under the joint energy dissipater along the water flow regime:

[0098] Design conditions, no energy dissipater, modification of the body under the joint energy dissipater along the water depth distribution is shown in table 5. Along the water depth using vertical floor measurement method, the same below.

[0099] Table 5 design conditions (reservoir water level for design flood level 1711m, total discharge 683m3 / s) modification of the body under the joint energy dissipater along the water depth distribution (no energy dissipater)

[0100]

[0101]

[0102] Among them, the energy dissipater and energy dissipater arrangement scheme along the water depth distribution measurement as follows:

[0103] Design conditions, no energy dissipater, modification of the body under the joint energy dissipater along the water flow velocity distribution is shown in table 6.

[0104] Table 6 design conditions (reservoir water level for design flood level 1711m, local open overflow dam section, discharge and sediment discharge hole, total discharge 683m3 / s) modification of the body under the joint energy dissipater along the water flow velocity distribution (no energy dissipater)​

[0105]

[0106] Based on the optimal layout selected from the previous energy dissipation scheme comparison, a T-shaped pier of 400mm is arranged at the end of the stilling basin to improve the flow pattern of the stilling basin and reduce the outlet velocity.

[0107] Under the design conditions, when the stilling basin is equipped with T-shaped piers, the water depth distribution along the stilling basin under the modified shape is shown in Table 7.

[0108] Table 7. Water depth distribution along the combined stilling basin under modified design conditions (reservoir water level is design flood level 1711m, total discharge 683m3 / s) (stilling basin is equipped with T-shaped piers).

[0109]

[0110] Among them: Measurement of flow velocity distribution in different flow layers under different energy dissipation structure arrangements:

[0111] Under the design conditions, when the stilling basin is equipped with T-shaped piers, the velocity distribution of different water flow layers in the combined stilling basin under the modified shape is shown in Table 8.

[0112] Table 8. Velocity distribution of different flow layers in the combined stilling basin under modified design conditions (reservoir water level is design flood level 1711m, total discharge 683m3 / s) (stilling basin is equipped with T-shaped piers).

[0113]

[0114] Analysis of energy dissipation results, as shown in Table 5, indicates that during periods without energy dissipation, the water flow entering the stilling basin is affected by the bend in the flow, resulting in a slight difference in water level between the concave and convex banks. Under design conditions, the water depth along the stilling basin is lower than that of the sidewalls. Within the stilling basin section from chainage 0+70.0m to 0+124.0m, there is varying degrees of water seepage on both the left and right banks. The water depth within this range is between 16 and 19m, with the maximum water depth occurring at chainage 0+90.0m, at 18.68m.

[0115] Table 7 shows that after the T-shaped piers of 400mm are installed in the stilling basin, the water depth distribution at the inlet sections of the overflow dam and the flood discharge and sediment flushing holes is uniform. After the water enters the stilling basin, the water flow in the bends weakens. After the shape of the combined stilling basin is modified, the water depth in all parts of the combined stilling basin shows an increasing trend. Under the design conditions, the water depth along the stilling basin is lower than that of the sidewalls. Within the stilling basin section from chainage 0+85.0m to 0+124.0m, there is varying degrees of water overflow. The water depth in this range is between 16 and 18m, with the maximum water depth occurring at chainage 0+90.0m, at 17.64m, indicating a significant decrease in water depth.

[0116] From table 6, without energy dissipation, with the increase of flow, the flow velocity of different water layers of the combined stilling basin shows an increasing trend. Compared with the flow velocity of the outlet section under the original scheme, the maximum point flow velocity at the outlet part of 0+232.0 m is 8.30 m / s.

[0117] From table 8, after arranging the T-shaped pier 400 in the stilling basin, with the increase of flow, the flow velocity of different water layers of the combined stilling basin shows an increasing trend. Compared with the flow velocity of the outlet section under the condition without energy dissipation, after arranging the T-shaped pier 400, the maximum point flow velocity under the design condition is reduced, wherein the design condition is 7.86 m / s, and the effect of the T-shaped pier is remarkable.

[0118] After arranging the T-shaped pier 400 with the optimal size in the stilling basin, the flow state of water flow in the stilling basin can be effectively improved. Under the design, the water depth along the way is lower than the side wall. The water depth in the range of pile numbers of 0+85.0 m~0+124.0 m in the stilling basin section is distributed between 16 m and 18 m, and the maximum water depth occurs at the pile number of 0+90.0, and the water depth is 17.64 m. Compared with the condition without energy dissipation, the outlet flow velocity is reduced, and the energy dissipation effect is remarkable. The T-shaped pier 400 has a high-efficiency energy dissipation and flow guiding effect on the water flow in the stilling basin. The improved stilling basin can reduce the intensity and range of the downstream deflection wave. The overall water flow state is more stable than that under the condition without energy dissipation, and the energy dissipation rate of the stilling basin is higher than that under the condition without energy dissipation.

[0119] The original technical scheme is a T-shaped pier 400 energy dissipation device, which is usually made of traditional materials (such as concrete or metal). The T-shaped pier 400 made of glass fiber composite material or carbon fiber composite material is the same as the T-shaped pier 400 energy dissipation device in the original technical scheme, which is composed of a front pier and a leg, one end of the leg is connected with the front pier in a T shape, and the other end is not connected. And the specific implementation mode of the corresponding technical scheme of the T-shaped pier energy dissipation device made of glass fiber composite material or carbon fiber composite material is the same effect.

[0120] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above examples, and the above examples and descriptions in the specification are only preferred examples of the present application and are not intended to limit the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. An energy dissipation and flow stabilization device applied to a curved stilling basin, comprising an inlet straight section (100), characterized in that: The straight section (100) at the inlet is fixedly connected to a curved section (200) to guide the water flow to change direction and form a preset flow pattern; The downstream end of the curved section (200) is fixedly connected to an outlet adjustment section (300), and multiple T-shaped piers (400) are spaced apart within the outlet adjustment section (300), wherein: It also includes measuring equipment and a layout simulation library. The layout simulation library is used to simulate the linear relationship between the water flow data and the layout of the T-shaped piers (400) after training. The measuring equipment is used to measure the water flow data under the current working condition and output the layout of the T-shaped piers (400) to the layout of the T-shaped piers (400). The T-shaped piers (400) are laid out on the outlet adjustment section (300) according to the layout, which is used to correct the flow pattern of the water flow that deviates after the bend of the curve section (200) and to divide the concentrated water flow into multiple secondary water flows.

2. The energy dissipation and flow stabilization device applied to a curved stilling basin according to claim 1, characterized in that: The T-shaped pier (400) consists of a front pier (401) and a support leg (402), with one end of the support leg (402) connected to the front pier (401) in a T-shape.

3. The energy dissipation and flow stabilization device applied to a curved stilling basin according to claim 1, characterized in that: The curved section (200) where the inlet straight section (100) and the outlet adjustment section (300) are smoothly connected forms a curved energy dissipation pool at both ends to adapt to the rugged terrain.

4. The energy dissipation and flow stabilization device applied to a curved stilling basin according to claim 3, characterized in that: The curved section (200) adopts a smooth curve shape, and its radius of curvature is determined according to the terrain conditions, water flow velocity and turning angle of the area where the stilling basin is located.

5. The energy dissipation and flow stabilization device applied to a curved stilling basin according to claim 1, characterized in that: The outlet adjustment section (300) adopts a gradually widened micro-curved structure, with its cross-sectional profile matching the end of the convex bank (220) and maintaining a smooth transition shape along the water flow direction.

6. The energy dissipation and flow stabilization device applied to a curved stilling basin according to claim 2, characterized in that: The T-shaped piers (400) are configured in multiple ways, and each T-shaped pier (400) is arranged sequentially along the water flow direction of the outlet adjustment section (300).

7. The energy dissipation and flow stabilization device applied to a curved stilling basin according to claim 1, characterized in that: The measuring equipment includes water depth measuring instruments, flow velocity measuring instruments, and flow rate measuring instruments.

8. The energy dissipation and flow stabilization device applied to a curved stilling basin according to claim 1, characterized in that: The layout simulation library includes a curved stilling basin under different working conditions by changing the water flow conditions, including flow rate and water level. The water depth, velocity, and pressure data of the curved stilling basin under different working conditions are measured by measuring equipment. Based on the evaluation indicators of water flow pattern, average outlet velocity, water depth and velocity in typical cross-sections, the arrangement form of the T-shaped piers is determined.

9. The energy dissipation and flow stabilization device applied to a curved stilling basin according to claim 1, characterized in that: The T-shaped pier (400) is made of glass fiber composite material.

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