阅读说明：本技术 一种带有底部消力池的鱼道进口分散补水系统布置方法 (Arrangement method of fishway inlet dispersed water replenishing system with bottom stilling pool ) 是由 祝龙 宣国祥 李云 黄岳 周冬卉 王晓刚 刘本芹 陈莹颖 金英 胡乔一 于 2019-09-16 设计创作，主要内容包括：本发明是一种带有底部消力池的鱼道进口分散补水系统布置方法,包括以下步骤：自上游水库设置补水管道,通过钢管引水至鱼道进口附近；在鱼道进口矩形渠道段的底部开挖设置补水消力池；利用补水管道引流至消力池,补水水流经消能后从顶部冒出,对鱼道进口补水,满足诱鱼需求。本发明的优点在于：不额外占用整体场地空间；兼具传统集中补水和分散补水的优点,达到了既增大进口水流流速,又对上溯鱼类影响甚小的效果；补水消力系统结构布置简单,可根据具体工程进行适当调整。(the invention relates to a method for arranging a fishway inlet dispersed water replenishing system with a bottom stilling pool, which comprises the following steps: arranging a water replenishing pipeline from an upstream reservoir, and guiding water to the position near the fishway inlet through a steel pipe; excavating a water replenishing stilling pool at the bottom of the rectangular channel section at the fishway inlet; and the water replenishing pipeline is utilized to drain water to the stilling pool, and water replenishing water flows out from the top after energy dissipation, so that water is replenished to the fishway inlet, and the fish luring requirement is met. The invention has the advantages that: the whole field space is not additionally occupied; the system has the advantages of both traditional centralized water replenishing and decentralized water replenishing, and achieves the effects of increasing the flow velocity of inlet water flow and having little influence on upstream fishes; the water replenishing and power eliminating system is simple in structural arrangement and can be properly adjusted according to specific projects.)

1. A method for arranging a fishway inlet dispersing and water supplementing system with a bottom stilling pool is characterized by comprising the following steps:

(1) Arranging a water replenishing pipeline from an upstream reservoir, and guiding water to the position near the fishway inlet through a steel pipe;

(2) Excavating a water replenishing stilling pool at the bottom of the rectangular channel section at the fishway inlet;

(3) The designed water replenishing amount is drained to a water replenishing stilling pool by utilizing a water replenishing pipeline, and the water replenishing water flows out from the top after energy dissipation to replenish water at the fishway inlet;

(4) energy dissipation measures are arranged in the water replenishing and stilling pool, the centralized outflow energy of the steel pipes is reduced, and the on-way outflow quantity is adjusted;

(5) the energy dissipation measures comprise: a longitudinal water outlet branch hole is formed in the middle upper portion of the water replenishing stilling pool, and a water stabilizing layer with a certain thickness is reserved above the water outlet branch hole so that water flow can be uniformly and stably emitted;

(6) The top of the water replenishing and stilling pool is provided with a fish blocking grid, so that upstream fishes are prevented from drilling into the water replenishing and stilling pool;

(7) Set up the moisturizing governing valve on foretell moisturizing pipeline to the homoenergetic carries out appropriate amount moisturizing under different water level operating modes, satisfies the demand of luring fish.

2. The method for arranging the fishway inlet decentralized water charging system with the bottom stilling basin as claimed in claim 1, wherein: the designed water supplement amount calculation formula is as follows:

(B_j×H_j×V_g-Q_y)≤Q_b≤(B_j×H_j×V_l-Q_y)；

the calculation formula of the minimum pipe diameter d _min of the water replenishing pipeline is as follows:

The water replenishing stilling pool is arranged according to the following principle:

a) The water replenishing stilling pool is arranged at a rectangular channel section at the fishway inlet, and the stilling pool is excavated at the bottom of the channel for arrangement;

b) the depth of the stilling pool is 1.5-2.0 m and is not less than 2 times of the pipe diameter;

c) The width of the stilling pool is equal to the width of the inlet channel; the length is arranged along the water flow direction;

d) Leading water from an upstream reservoir area through a water supplementing steel pipe, and connecting a pipeline outlet with the bottom of a water supplementing stilling pool to ensure that large-flow-speed concentrated water flow in a pipeline can fully dissipate energy in the stilling pool;

e) the water flow from the top of the stilling pool is uniform and stable, and the flow rate of the water flow is controlled below the median of the induction flow rate of the target fish;

The surface area A _min calculation formula of the water replenishing stilling pool

The fish blocking grating is arranged in the following way:

The water replenishing stilling pool is characterized in that a fish blocking grid is arranged on the surface of the water replenishing stilling pool, the fish blocking grid can be made of steel, and the size of grid holes is set according to the body shape of fish passing objects in main fish passing seasons so as to block the smallest fish passing objects.

Technical Field

the invention provides a fishway inlet dispersed water replenishing system arrangement method with a bottom stilling pool, and belongs to the field of fishway engineering in dam-crossing buildings.

background

9.8 thousands of reservoir dams exist in China, which bring huge social and economic benefits to human beings, but also form barriers to migration of fishes upstream and downstream of a hub, and cause disruption of habitat and change of fish inhabitation environment. Along with the development of economy in China, the nation pays more and more attention to ecological protection, and in the field of environment of key development of the outline of the development of long-term science and technology development planning in China (2006-2020), recovery and reconstruction of ecological system functions in ecological vulnerable areas are definitely regarded as the priority topic. In water conservancy construction, attention is paid to a migration route for protecting migratory aquatic organisms, harmony and coexistence of human and nature are realized, and the method is extremely important for realizing sustainable development of water conservancy. In terms of engineering measures for protecting migratory aquatic organisms, the construction of fishway engineering is an important means and measure for solving the problem.

the fishway is responsible for communicating upstream and downstream fish migration channels of the dam site and guaranteeing the watershed water ecological environment, and besides the condition that the water flow inside the pond chamber meets the requirement of the target fishes for upstream tracing, the hydraulic design of the fishway inlet is of great importance. The fishway inlet can enable fishes to quickly find and smoothly enter the fishway and is the key of fishway success and failure; if the conditions of the inlet water flow are not good, even if the conditions of passing the fish in the fishway are good, the condition is also vain.

Compared with the width of the whole river channel, the fishway inlet dimension is very small and is a genuine 'needle eye engineering', and an important task of the fishway inlet design is to strengthen the fish luring, guiding and collecting effects of the fishway inlet design so as to improve the fish feeding capacity. Compared with sound, light and electricity, the fish is more sensitive to water flow perception, so that a good fish way inlet design can generate enough water flow velocity to be perceived by nearby fishes, and then the fishes enter the fish way to perform migration and backtrack. However, in practical design, in order to meet the requirement of on-way energy dissipation, fishways are often designed into multistage pool chambers with contraction control sections, which is the principle of the vertically slotted fishways widely adopted in the engineering design in China at present, and the width of the control sections is usually narrow and is only dozens of centimeters. This directly leads to a conflicting and constraining problem: the larger the width of the fishway inlet is, the easier the fish in the river channel can be found and enter the fishway; the wider the inlet, the smaller the cross-sectional flow velocity is relative to the internal control cross-section of the fishway, and the small self-running flow of the fishway possibly causes the inlet flow velocity of the fishway to be lower than the induction flow velocity of the fishes in the river channel, thus being very unfavorable for attracting the fishes. Some experts have noticed this and proposed some measures for water replenishing of fishway, but there are still the following problems to be solved: 1. according to the traditional centralized water supplementing mode, a water supplementing pipe is directly arranged at a fishway inlet, a centralized outflow is formed at the outlet of the water supplementing pipe, the flow velocity of water flow is high, the flow state of the water flow near the fishway inlet is often disordered, vortex water flow is generated, the direction sense of fishes is lost, and the fishes are influenced; 2. a fishway on-way dispersion water replenishing system has a relatively complex water replenishing pipe network, and each branch pipe pipeline also needs to be provided with complex equipment such as a valve, a flow monitoring control instrument and the like, so that the operation is complicated, the outflow uniformity of each branch pipe is high, and the flow state of outlet water flow is difficult to control; in addition, the water supplement in the fishway pool chamber can increase the flow of the local fishway pool chamber, so that the water flow velocity of the downstream fishway control section of the water supplement area is increased, even the condition of exceeding the standard is avoided, and smooth upward tracing of the fishes is not facilitated.

disclosure of Invention

The technical problem to be solved by the invention is as follows: under the premise of not influencing the water flow condition in the fishway pool chamber and ensuring that the fishway inlet has proper water flow state, the water flow speed at the fishway inlet is improved, and good fish luring water flow conditions are formed.

The invention discloses an arrangement method of a fishway inlet dispersive water-replenishing energy-dissipating system with a stilling pool.

specifically, the method comprises the following steps:

(1) Arranging a water replenishing pipeline from an upstream reservoir, and guiding water to the position near the fishway inlet through a steel pipe;

(2) Excavating a water replenishing stilling pool at the bottom of the rectangular channel section at the fishway inlet;

(3) draining to a water replenishing stilling pool by using a water replenishing pipeline, discharging water from the top after energy dissipation, and replenishing water to the fishway inlet;

(4) Energy dissipation measures are arranged in the water replenishing and stilling pool, the centralized outflow energy of the steel pipes is reduced, and the on-way outflow quantity is adjusted;

(5) The energy dissipation measures comprise: a longitudinal water outlet branch hole is formed in the middle upper portion of the water replenishing stilling pool, and a water stabilizing layer with a certain thickness is reserved above the water outlet branch hole so that water flow can be uniformly and stably emitted;

(6) The top of the water replenishing and stilling pool is provided with a fish blocking grid, so that upstream fishes are prevented from drilling into the water replenishing and stilling pool;

(7) the water replenishing regulating valve is arranged on the water replenishing pipeline, so that proper water replenishing can be carried out under different water level working conditions, and the fish luring requirement is met.

The principle and specific control parameters of the technical scheme provided by the invention are as follows:

The principle of the technical scheme provided by the invention is as follows: the fishway water supply flow is concentrated near the fishway inlet, and the water flow velocity of the fishway inlet area is improved as much as possible on the premise of not influencing the water flow state in the fishway pool chamber; by arranging the water replenishing stilling pool, the water outlet flow of the water replenishing pipeline is controlled to uniformly emerge from the top of the water replenishing stilling pool, so that the flow velocity at the outlet of the stilling pool is smaller than the fish induction flow velocity median, the flow state of turbulent water flow is not generated, and the upstream fish is not interfered; and the flow velocity at the fishway inlet is more than or equal to the median of the fish induction flow velocity, so that the water replenishing effect without interference or attraction is achieved.

The technical scheme provided by the invention comprises the following specific control parameters:

(1) Design water supplement amount Q _b

during the operation of the project, the flow rate V _j of the water at the inlet of the fishway is preferably not less than the median V _g of the induced flow rate of the main fish passing objects, and is controlled not to be more than the median V _l of the critical swimming speed of the main fish passing objects, so that the optimal fish luring effect is achieved on the premise of saving the water supplement amount, namely the water supplement amount Q _b is adjusted according to the requirement of the flow rate V _j of the water at the inlet of the fishway

V_g≤V_j≤V_l (1)

assuming that the rectangular channel width B _j at the fishway inlet, the running water depth H _j at the fishway inlet and the normal running flow Q _y in the fishway, the flow speed of the water flow at the fishway inlet is V _j ═ Q _b + Q _y)/(B _j X H _j) (2)

Substituting the formula (1), controlling the water supplement quantity of the fishway inlet according to the formula (3):

(B_j×H_j×V_g-Q_y)≤Q_b≤(B_j×H_j×V_l-Q_y) (3)

(2) Minimum pipe diameter d _min of water compensating pipe

The reasonable water replenishing pipe diameter is as small as possible on the basis of meeting the water replenishing operation requirement of the fishway inlet, so that the most economical and reasonable investment effect is achieved. According to the invention, the design principle of the minimum pipe diameter of the water replenishing pipe is provided according to the calculation and analysis of the pipeline hydraulics, and the formula (4) is as follows:

in the formula, g is gravity acceleration, H _k is an upstream reservoir water level (upstream inlet water level of a water conduit), H _y is a downstream fishway inlet operating water level, the highest value is taken when multiple operating water levels are used, Q _b is fishway water replenishing flow, the maximum water replenishing quantity is taken when multiple water replenishing quantities are used, d _min is the minimum pipe diameter of the water conduit, l is the length of the water conduit, and Σ ξ is an estimated value of the local resistance coefficient of the water conduit.

In actual arrangement, according to the formula (4), the minimum pipe diameter d _min is obtained through trial calculation, and a certain flow allowance is reserved for selecting the pipe diameter of the water replenishing pipe.

(3) water replenishing stilling pool arrangement

the principle of the arrangement of the stilling pool in the water replenishing stilling pool provided by the invention is as follows: the water replenishing flow is ensured to fully dissipate energy, the water flow at the top is uniform and stable, the whole surface is formed to disperse and flow out, and the flow velocity of the water flow is less than the median of the induction flow velocity of the main fish passing object.

a) the water replenishing stilling pool is arranged at a rectangular channel section at the fishway inlet and is arranged by excavating at the bottom of the channel;

b) The depth of the water replenishing stilling pool is 1.5-2.0 m and is not less than 2 times of the pipe diameter;

c) The width of the water replenishing absorption basin is equal to the width of the inlet channel; the length of the water flow is arranged along the water flow direction, and the water flow is properly lengthened along the length direction, so that the flow velocity distribution which is slightly reduced from the fishway inlet to the inside is formed at the channel section at the fishway inlet, the upward-tracing fish gradually reduces the body force consumption in the advancing process, and the upward tracing along the fishway pool chamber can be continued after the fish entering the fishway can be properly adjusted to have a rest;

d) When the fishway is supplemented with water, water is introduced from an upstream reservoir area through a water supplementing steel pipe, and the outlet of the pipeline is connected with the bottom of the water supplementing stilling basin, so that the concentrated water flow with high flow speed in the pipeline can be fully dissipated in the water supplementing stilling basin;

e) And adjusting the arrangement of energy dissipation measures in the water replenishing stilling pool, ensuring that the water flow from the top of the water replenishing stilling pool is uniform and stable, and controlling the water flow speed to be below the medium value of the target fish induced flow speed.

In addition, the invention also provides a fishway inlet water replenishing energy dissipater with a bottom stilling pool,

The method specifically comprises the following steps:

The water inlet, the cistern, bottom flat slope, flat slope energy dissipation bank, bottom slope, slope energy dissipation bank, the branch hole of going out water, water inlet low reaches connect one section bottom flat slope, the flat slope end sets up a flat slope energy dissipation bank, slope energy dissipation bank sets up in the slope middle section.

The water replenishing flow enters the reservoir from the water inlet, can be absorbed on the bottom flat slope and the flat slope energy dissipation ridge and then flows to the bottom slope and the inclined slope energy dissipation ridge, and after the whole reservoir is fully stored, the flow flows upwards from the water outlet branch hole.

the top surface of the water outlet branch hole is positioned 30cm below the designed bottom surface line of the bottom surface of the fishway inlet.

The bottom slope of the bottom slope is 3-10 degrees, and the optimal bottom slope for the four Chinese carps is 4 degrees.

the average flow velocity of the water flow is slightly lower due to the deeper reservoir at the water inlet end, and slightly higher due to the shallower reservoir at the end far away from the water inlet end.

(4) water outlet surface area A _min of water replenishing stilling pool

the flow velocity of water flow emerging from the water replenishing stilling pool is controlled below the median induction flow velocity of target fishes, the upstream fishes are prevented from being influenced by water replenishing flow and wandering, and the aim of replenishing water invisibly is fulfilled. Therefore, the surface area of the water replenishing absorption basin meets the requirement of the formula (5):

In the formula, A _min is the minimum water outlet area of the water replenishing stilling pool, B is the effective pool width of the water replenishing stilling pool, L is the effective pool length of the water replenishing stilling pool, Q _b is the water replenishing flow of the fishway, if a plurality of water replenishing amounts exist, the maximum value is taken, and V _g is the medium value of the induced flow of the main fish passing object of the fishway.

(5) Fish-blocking grille arrangement

the water replenishing stilling pool top surface is provided with the fish blocking grating above the water replenishing branch holes, the fish blocking grating is made of steel grating, the size of the grating hole is set according to the fish body shape of the fish object in the main fish passing season, if the fish body shape in the river channel is small, the small grating hole is taken, if the fish body shape in the fish channel is large, the large grating hole is taken, the grating hole is not larger than 2cm multiplied by 2cm, and the situation that the small fish in the body shape is drilled into the stilling pool is avoided.

The invention has the beneficial effects that:

1. The design of the invention fully utilizes the bottom of the channel section of the fishway inlet to arrange the water replenishing stilling pool without additionally occupying the whole field space;

2. the method has the advantages of both traditional centralized water replenishing and decentralized water replenishing, namely, on the premise of not disturbing the water flow condition of the pool chamber in the fishway, decentralized uniform and stable water replenishing water flow is formed in the fishway inlet area, and the water replenishing water flow velocity is smaller than the induction flow velocity of target fishes, so that the effects of increasing the inlet water flow velocity and having little influence on upstream fishes are achieved;

3. The water replenishing and stilling system is relatively simple in structural arrangement and convenient to operate, stilling measures in the stilling pool can be properly adjusted according to specific engineering, and the water replenishing and stilling system is high in universality and reference.

Drawings

FIG. 1 is a schematic diagram of the general arrangement of a fishway inlet with a water supplementing and energy dissipating system;

FIG. 2 is a schematic diagram of the arrangement of the water replenishing stilling pool in a vertical plane;

FIG. 3 is a schematic plan view of the water replenishing stilling pool of the present invention;

Wherein, 1 moisturizing pipeline, 2 fishways, 3 moisturizing governing valves, 4 moisturizing stilling ponds, 5 access doors, 6 fishway imports, 7 block the fish grid, 8 play water branch holes, 9 water inlets, 10 cistern, 11 bottom flat slopes, 12 flat slope energy dissipation banks, 13 bottom slopes, 14 slope energy dissipation banks.

Detailed Description

The embodiments are provided below in conjunction with the accompanying drawings and the invention is described in detail.