Tilting weir control system, tilting weir control method and program

Abstract

To provide a tilting weir control system that employs a tilting weir, which can obtain stable flow before and after the weir, reduce energy loss caused by the weir, and increase durability of the weir when adjusting the amount of water taken from a waterway such as a river, and which can ensure required amount of water taken from the waterway by adjusting the tilting degree of the tilting weir.SOLUTION: A tilting weir control system includes a limit water depth calculation part 10 that calculates the limit water depth hc from the overflow rate Q of the tilting weir, a weir height calculation part 12 that calculates the weir height hd for complete overflow and submerged overflow, an overflow state determination part 13 that determines the overflow state, a weir gradient calculation part 14 that calculates the weir gradient sin θ of the tilting weir from the weir height hd based on the results of the determination, a weir gradient control part 4 that controls the weir gradient of the tilting weir based on the weir gradient, and a weir tilting part 5 that can change the weir gradient of the tilting weir based on control signals from the weir gradient control part 4.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a tipping weir control system, a tipping weir control method, and a program for controlling the weir inclination of a tipping weir to obtain the required water intake volume from a waterway such as a river while adjusting the water level upstream of the weir and the overflow volume. [Background technology]

[0002] Conventionally, when regulating the amount of water taken from a waterway such as a river, a gate weir has often been used, and the method of controlling its opening degree has been adopted. For example, Patent Document 1 discloses a flow control device that controls the amount of water flowing out of the bottom end of a gate by raising and lowering the gate. This flow control device uses the measured value of the water depth on the primary side of the gate, the predicted set value of the water depth on the secondary side of the gate, and the target flow rate as a target value for the gate operation opening, and controls the gate opening to quickly approach the target flow rate in the initial operation of the gate. In addition, Patent Document 2 discloses an invention relating to a flow meter that can measure the water head regardless of the opening degree of a movable overflow weir by using a throw-in type water level gauge integrated into the movable overflow weir, which allows water to flow out from the top end rather than the bottom end of the weir. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2012-225049 A [Patent Document 2] JP 2002-340636 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the invention disclosed in Patent Document 1, a gate that flows out from the bottom end is used as a gate weir, and the water level upstream of the gate and the flow rate at the bottom of the gate are controlled by raising and lowering the gate. However, it is known that gates are not suitable for adjusting small flow rates, they capture floating objects, and they are heavier than weirs, so they require a large power to raise and lower (Reference 1: Fujiyama Munetaka, Nakaya Tetsuro: Experimental Study on the Hydraulic Characteristics of Check Gates with Combined Underflow and Overflow, Journal of the Japan Society of Civil Engineers, B1 (Hydraulic Engineering), Vol. 75, No. 2, pp. I_457-I_462). Therefore, the flow from the upstream of the gate is narrowed to flow out from the gap at the bottom end of the gate, so the outflow speed is large and energy loss cannot be ignored. In addition, the bottom end of the gate and the floor of the flow path are eroded by the outflow of water, so maintenance and repair are required frequently, and there is a concern that the accuracy of the predicted setting value of the secondary side water depth of the gate may decrease, and at the same time, there is a possibility that the durability of the gate itself may be low. Furthermore, because Patent Document 2 employs an overflow movable weir as the weir, the runoff water flows over the top of the weir, so the flow path when it goes over the weir is larger than in the case of a gate, and the flow rate is therefore slower.However, the invention disclosed in Patent Document 2 is an invention related to a flow meter that uses a throw-in type water level gauge integrated with an overflow movable weir, and although it is possible to measure the water level upstream of the overflow movable weir, there is a problem in that it is not possible to control the weir height of the overflow movable weir.

[0005] The present invention has been made to address such conventional circumstances, and aims to provide a tipping weir control system, a tipping weir control method, and a program for the same, which employs a tipping weir that, when adjusting the amount of water taken from a waterway such as a river, can suppress the capture of floating matter, reduce the power required for raising and lowering operations, obtain a stable flow before and after the weir, reduce energy loss due to the weir, and increase the durability of the weir, and which can ensure the necessary amount of water taken from a waterway by adjusting the weir inclination of the tipping weir. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, the first invention is a tipping weir control system that controls the weir inclination of a tipping weir for taking water from a waterway, and is characterized in having a critical water depth calculation unit that calculates the critical water depth from the overflow rate of the tipping weir, a weir height calculation unit that calculates the weir height in the case of complete overflow and in the case of submerged overflow, an overflow state determination unit that determines whether complete overflow is complete or submerged overflow, a weir inclination calculation unit that calculates a target value of the weir inclination from the weir height for complete overflow or submerged overflow according to the result of the determination, a weir inclination control unit that generates a control signal to control the weir inclination based on the target value, and a weir tilting unit that can change the weir inclination by the control signal generated by the weir inclination control unit. In a tipping weir control system configured in this manner, the weir height calculation unit calculates the weir height of the tipping weir in both cases of complete overflow and submerged overflow, calculated by subtracting the water intake volume from the flow rate of the waterway, the overflow state determination unit determines whether the overflow state is complete overflow or submerged overflow, the weir gradient calculation unit calculates a target value for the weir gradient of the tipping weir from the weir height in accordance with the determination result, the weir gradient control unit generates a control signal that controls the weir gradient based on the target value, and the weir tilting unit acts to change the weir gradient based on the control signal.

[0007] The second invention, the overturning weir control system, is characterized in that in the first invention, it has a weir height limit value calculation unit that calculates the weir height limit value which is the limit at which submerged overflow occurs, and the overflow state determination unit uses the weir height limit value to determine whether complete overflow or submerged overflow is occurring. In the thus configured overturning weir control system, the weir height limit value calculation unit calculates the weir height limit value that is the boundary between complete overflow and submerged overflow, thereby assisting the overflow state determination unit in determining whether the overflow is complete or submerged overflow.

[0008] A third invention, a tipping weir control method, is a tipping weir control method for controlling the weir inclination of a tipping weir for taking water from a waterway, and is characterized by having a critical water depth calculation step for calculating a critical water depth from the overflow rate of the tipping weir, a provisional weir height calculation step for provisionally calculating the weir height for the cases of complete overflow and submerged overflow, an overflow state determination step for determining whether complete overflow is complete or submerged overflow, a weir height determination step for determining the weir height for complete overflow or submerged overflow in accordance with the results of the determination, a weir inclination calculation step for calculating a target value of the weir inclination from the weir height for complete overflow or submerged overflow determined in the weir height determination step, a control signal generation step for generating a control signal for the weir inclination based on the target value, and a weir tilting step for changing the weir inclination using the control signal. The overturning weir control method configured in this manner is a method invention corresponding to the first invention, which is a product invention, and therefore each of the steps corresponding to the components in the first invention has the same effect.

[0009] The fourth invention, a method for controlling a overturning weir, is characterized in that, in the third invention, it includes a weir height limit value calculation step for calculating the weir height limit value which is the limit at which submerged overflow occurs, and the weir height limit value is used to determine whether complete overflow or submerged overflow is present in the overflow state determination step. The overturning weir control method configured in this manner acts to assist in the determination of whether a complete overflow or a submerged overflow occurs in the overflow condition determination process by calculating the weir height limit value at which a submerged overflow occurs in the weir height limit value calculation process.

[0010] The fifth aspect of the present invention is a tipping dam control program, A program executed by a computer to control the weir inclination of a tipping weir for taking water from a waterway, the program comprising: a critical water depth calculation process for calculating a critical water depth from the overflow rate of the tipping weir; a provisional weir height calculation process for provisionally calculating the weir height for the cases of complete overflow and submerged overflow; an overflow state determination process for determining whether complete overflow is complete or submerged overflow; a weir height determination process for determining the weir height for complete overflow or submerged overflow based on the results of the determination; a weir inclination calculation process for calculating a target value of the weir inclination from the weir height for complete overflow or submerged overflow determined in the weir height determination process; a control signal generation process for generating a control signal for the weir inclination based on the target value; and a weir tilting process for changing the weir inclination using the control signal. The overturning dam control program configured in this manner is a program invention corresponding to the third invention, which is a method invention, and therefore when this program invention is executed using a computer, it has the same effects as each of the steps constituting the third invention.

[0011] The sixth invention is a overturning weir control program, which, in the fifth invention, is characterized in that it includes a weir height limit value calculation step for calculating the weir height limit value, which is the limit at which submerged overflow occurs, and uses the weir height limit value to determine whether complete overflow or submerged overflow is occurring in the overflow state determination step. When the overturning weir control program configured in this manner is executed using a computer, the weir height limit value calculation process calculates the weir height limit value at which submerged overflow occurs, thereby assisting in the determination of whether the overflow is complete or submerged overflow in the overflow condition determination process. Effect of the Invention

[0012] In the tipping weir control system of the first invention, a tipping weir is used as the weir, so it is possible to form a stable water flow from the upper end of the tipping weir to the downstream side, and there is no adverse effect such as turbulence on the flow upstream of the tipping weir. Also, unlike a gate weir, water does not run off from the gap between the bottom of the gate and the floor of the channel, but flows out from the top of the weir in proportion to the overflow rate, so there is less energy loss associated with a narrow channel and less erosion of the gate and channel floor due to accelerated runoff water. Furthermore, since the weir inclination of the overturning weir can be controlled while taking into consideration whether the flow will be complete overflow or submerged overflow depending on the flow rate of the waterway and the amount of water taken from the waterway, more precise control is possible.

[0013] The overturning weir control system of the second invention has a weir height limit value calculation unit that calculates the weir height limit value, which is the limit at which submerged overflow occurs, making it easy to distinguish between complete overflow and submerged overflow.

[0014] The third and fifth inventions are based on the first invention as a method invention and a program invention, respectively, and therefore have the same effects as the first invention.

[0015] The fourth and sixth inventions are inventions which are based on the second invention as a method invention and a program invention, respectively, and therefore have the same effects as the second invention. [Brief description of the drawings]

[0016] [Figure 1] This is a conceptual diagram showing the relative positions of a waterway such as a river, a tipping weir, and a water intake channel. [Diagram 2] FIG. 1 is a conceptual diagram showing a state in which complete overflow occurs in a waterway. [Diagram 3] FIG. 1 is a conceptual diagram showing an example of an underwater overflow occurring in a waterway. [Figure 4] FIG. 1 is a block diagram of a tipping weir control system according to a first embodiment of the present invention. [Diagram 5] FIG. 2 is a flow diagram relating to control of the weir inclination of a tipping weir executed by the tipping weir control system according to the first embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, a tipping weir control system according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 5. FIG. Figure 1 is a conceptual diagram showing the relative positions of a waterway such as a river, a tipping weir, and a water intake channel, and Figures 2 and 3 are conceptual diagrams showing situations in which complete overflow and submerged overflow have occurred in the waterway, respectively.

[0018] In Fig. 1, a waterway 20 to which the present invention is applied has a tipping weir 22 installed midway, and water is taken from an intake channel 21 installed immediately upstream of the weir. The waterway 20 may be a river or an artificially constructed one. The purpose of taking water corresponds to securing irrigation water for agricultural fields or water for hydroelectric power generation. As shown in the lower part of Figure 1, if the waterway flow rate in the waterway 20 is Q0, the intake water volume is Qe, and the overflow volume of the overturning weir 22 is Q, then Q is the difference between Q0 and Qe. Therefore, when ensuring the intake volume Qe required for the intake channel 21, if the channel flow rate Q0 decreases, the tipping weir 22 must be brought closer to vertical (perpendicular) in order to reduce the overflow volume Q, and if the channel flow rate Q0 increases, the tipping weir 22 must be tilted from the vertical in order to increase the overflow volume. Furthermore, when the overflow volume is small, it will be a complete overflow, as will be explained with reference to Figure 2, but if the overflow volume increases, it will transition to a submerged overflow, as will be explained with reference to Figure 3, and therefore the overflow volume Q must be evaluated according to the type of overflow and the weir inclination of the tipping weir 22 must be controlled. The present invention controls the weir inclination of the overturning weir 22 to control the overflow rate Q of the overturning weir 22 in response to an increase or decrease in the water channel flow rate Q0 in order to ensure the intake rate Qe required for the intake channel 21.

[0019] Next, complete overflow at the tipping weir 22 will be described with reference to FIG. First, complete overflow means an overflow in which the water level downstream of the weir (overturning weir 22) is lower than the weir crest 23, and the overflow rate R per unit width for a particular weir (Q / B: hereinafter, the channel width (= weir width) of the waterway 20 is designated as B) is uniquely determined by the overflow depth indicated by the symbol h (the water level upstream of the weir based on the weir crest 23, hereinafter referred to as the overflow depth). In FIG. 2, the left side of the overturning weir 22 is the upstream side of the weir, and the right side is the downstream side of the weir. In addition, symbol H1 is the water depth upstream of the weir, symbol h is the overflow water depth as mentioned above, and h d is the weir height. Furthermore, the symbol L is the length (weir length) of the overturning weir 22, so h d can be expressed as Lsinθ, and H1 is h and h d It can be expressed as the sum of

[0020] Next, the submerged overflow at the tipping weir 22 will be described with reference to FIG. First, submerged overflow means an overflow in which the water level downstream of the weir (overturning weir 22) is higher than the weir crest 23, and the overflow rate R(Q / B) per unit width for a particular weir is determined by the water level upstream of the weir h1 and the water level downstream of the weir h2 based on the weir crest 23. In Fig. 3, the upstream and downstream of the weir of the waterway 20 are the same as those in Fig. 2, and the configurations described using Fig. 2 are given the same reference numerals and their description is omitted. Reference numeral h1 denotes the upstream water level of the weir based on the weir crest 23 at the time of submerged overflow (hereinafter simply referred to as the upstream water level of the weir), and h2 denotes the downstream water level of the weir based on the weir crest 23 (hereinafter simply referred to as the downstream water level of the weir). Reference numeral H2 denotes the water depth downstream of the weir, and the difference between h2 and h d It can also be expressed as the sum of In the overturning weir control system 1 according to the present embodiment, the weir height h is adjusted while determining whether the flow is a complete overflow or a submerged overflow as described above. d By calculating d =L·sinθ, and the weir gradient (sinθ) of the tipping weir 22 is calculated so as to achieve this weir gradient. The tipping weir control system 1 will now be described in detail with reference to FIGS.

[0021] Fig. 4 is a block diagram of a tipping weir control system according to a first embodiment of the present invention, and Fig. 5 is a flow diagram relating to the control of the weir inclination of a tipping weir executed by the tipping weir control system. Fig. 5 also shows the execution steps of the tipping weir control method and tipping weir control program of the present invention, and explaining the flow of calculations and data processing in the tipping weir control system 1 with reference to this figure is equivalent to explaining an embodiment of the tipping weir control method and tipping weir control program using a computer. In addition, in Figure 5, the symbols attached to the descriptions related to the steps indicated by "S" indicate the symbols of the components of the overturning weir control system 1 shown in Figure 4, and mean that each step is carried out by the component with that symbol.

[0022] In Fig. 4, the tipping weir control system 1 is composed of an input section 6, an output section 7, a calculation section 2, a database 3, a weir gradient control section 4, and a weir tilting section 5. This tipping weir control system 1 can be imagined as a system equipped with calculation circuits and storage devices capable of performing their respective functions within a computer server. In addition to the input section 6, output section 7, calculation section 2, weir gradient control section 4, and weir tilting section 5, the word "section" is often used in the explanation of this embodiment, but these can be thought of as corresponding to hardware such as a "device," "unit," or "circuit." The input unit 6 corresponds to a data receiving unit such as a receiving terminal for receiving data from other devices or an information and communication network, or a keyboard, and is used when storing data required for calculation by the calculation unit 2 in advance in the database 3, as described below. The output unit 7 corresponds to a display device, a transmission terminal to an information and communication network, or a transmitter that transfers data to other devices as a data transmission unit, and is used to output the calculation results calculated in the calculation unit 2 or the data stored in the database 3. The calculation unit 2, which will be explained using Figure 4, analyzes the flow conditions in the waterway 20 and determines whether it is complete overflow or submerged overflow, while calculating a target value for the weir gradient sin θ of the overturning weir 22 to ensure the intake volume Qe required in the intake channel 21 from the waterway flow rate Q0, and sends a signal regarding the target value to the weir gradient control unit 4.

[0023] Furthermore, the weir gradient control unit 4 generates a control signal using the target value of the weir gradient sin θ of the overturning weir 22 received from the calculation unit 2, and transmits the control signal to the weir tilting unit 5 to control it. The weir tilting unit 5 tilts the tipping weir 22 in response to a control signal received from the weir tilt control unit 4. The database 3 includes physical quantities such as the waterway gradient i and waterway width B required for the calculation of the weir gradient sinθ of the overturning weir 22 by the calculation unit 2, physical constants 15 or various constants 16 used in the calculation formula (empirical formula), as well as the weir height limit value h dA and dam height h d The calculation results such as are stored. Of these data, the data necessary for calculations in the calculation unit 2 is stored in advance in the database 3 via the input unit 6, and the results calculated in the calculation unit 2 are stored in the database 3 in a readable manner by the limit water depth calculation unit 10 of the calculation unit 2 involved in the calculation.

[0024] Hereinafter, with reference to FIG. 5 in addition to FIG. 4, a specific description will be given of how the weir gradient of the tipping weir 22 is calculated and controlled by the tipping weir control system 1 according to this embodiment. When operating the tipping weir control system 1 according to this embodiment, the channel flow rate Q0 and intake rate Qe in the channel 20 are given in advance, so the overflow rate Q can be determined, but whether the above-mentioned complete overflow or submerged overflow occurs is determined by the overflow rate Q and the flow in the channel 20 downstream of the tipping weir 22. Furthermore, the upstream water level (overflow depth) h based on the weir crest 23 of the tipping weir 22 in the case of complete overflow, and the upstream water level h1 and downstream water level h2 based on the weir crest 23 in the case of submerged overflow are physical quantities determined by the type of overflow. The weir height h dis a physical quantity that is interdependent with the overflow rate Q and these water levels. Therefore, in the toppling weir control system 1 according to the present embodiment, a target weir height h is calculated based on the occurrence conditions of submerged overflow, the overflow amount Q and the overflow depth in complete overflow, and the water levels upstream and downstream of the weir based on the weir crest 23 in submerged overflow. d A control signal is then sent from the weir gradient control unit 4 to the weir tilting unit 5 so as to achieve the weir gradient. The contents will be explained in detail below.

[0025] First, referring to FIG. 3, the condition for occurrence of submerged overflow is given by the following equation using the downstream water level h2 based on the weir crest 23. h2=0 (1) Also, referring to FIG. 3, the weir height h d and the water depth downstream of the weir, H2, the following relationship also holds: h2=H2-h d (2) Therefore, equation (1), which is the condition for the occurrence of submerged overflow, can be expressed as follows: h d =H2(3) Given the overflow volume Q, the critical water depth h c is determined as follows: R is the overflow rate per unit width at the tipping weir 22 and g is the acceleration due to gravity. Therefore, the limit depth h c has the dimension of length, but is a physical quantity that represents the overflow rate Q. h c =(R 2 / g) 1 / 3 where R=Q / B (3a)

[0026] In the tipping dam control system 1 according to the present embodiment, the critical water depth h is calculated by the critical water depth calculation unit 10 of the calculation unit 2 in step S1. cHere, the overflow rate Q is expressed as the difference between the channel flow rate Q0 and the intake rate Qe, so by storing these in advance in a readable manner in the database 3 via the input unit 6, these can be read out and calculated by the critical water depth calculation unit 10. In addition, the channel width B is stored in advance in the database 3 via the input unit 6 as a necessary physical quantity, and the gravitational acceleration g is also stored in advance as a necessary physical constant 15. Calculated limit depth h c is stored in the database 3 so as to be readable by the critical water depth calculation unit 10. Note that data calculated by other components of the calculation unit 2 are also stored in the database 3 so as to be readable by the respective components.

[0027] Next, assuming that the downstream side of the overturning weir 22 is a uniform flow in a wide rectangular cross-section channel with Manning's roughness coefficient n, channel gradient i, and channel width B, the water depth H2 downstream of the weir is determined as follows.

[0028]

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[0029] From this equation (4), the downstream water depth H2 corresponding to the overflow rate Q can be obtained. From this and equation (3), the weir height h d The limit value of h dA is obtained. Therefore, in the tipping dam control system 1, in step S2, the dam height limit value calculation unit 11 of the calculation unit 2 calculates the dam height limit value h dA At this time, the Manning's roughness coefficient n, the waterway gradient i, and the waterway width B are stored in advance in the database 3 via the input unit 6. The weir height limit value calculation unit 11 can also calculate the overflow volume Q in a similar manner. In addition, the inventors have found that in the case of complete overflow, the overflow water depth h and the weir height h are calculated based on the results of past experiments (Reference 2: US Bureau of Reclamation: Studies of overfall dams, Boulder Canyon Project, Final Reports, Bull. No. 3, 1948). d The ratio (h / hd ) has a boundary value of 3, and the state of complete overflow differs at this boundary. d We discovered through research that the formula for calculating the total overflow is different. Therefore, we decided to use this boundary value to classify the complete overflow state. Specifically, it can be expressed by the following formula.

[0030]

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[0031] Therefore, the condition for formula (3) and formula (5) to be compatible is the following formula (6).

[0032]

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[0033] So, h / h d >3 and h / h d The weir height h is calculated by dividing the two cases into two groups, i.e., complete overflow and submerged overflow, and the weir height h is calculated by dividing the two groups into two groups, i.e., complete overflow and submerged overflow. d Consider calculating the following: (a)h / h d If >3 (H1>4H2) In this case, complete overflow clearly occurs, and if an evaluation formula (empirical formula) is derived based on the experimental results of a vertical weir and an inclined weir (Reference 2), the following formula (7) is obtained.

[0034]

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[0035] Here, α=0.00034, β=−0.0091, γ=0.0736, δ=0.6723, and ε=0.0069, and these constants are stored in advance as various constants 16 in the database 3 via the input unit 6 so as to be readable. From this equation (7), h d When this formula is transformed into the formula (8), it becomes the following formula (8). In formula (8), H1=hd Since it is +h (see Figure 2), the h has been eliminated. These equations (7) and (8) were also obtained through the inventor's research.

[0036]

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[0037] Weir height h d In equation (8), which is a fourth-order equation for, the water depth H1 upstream of the weir is given in advance and stored in the database 3 via the input unit 6. Therefore, in step S3, the dam height calculation unit 12 of the calculation unit 2 of the overturning dam control system 1 reads out H1 and the constants α to ε from the database 3 and solves equation (8) to calculate the dam height h d Let's calculate it provisionally, but as mentioned above, h / h d If the flow rate is >3, complete overflow occurs, and it is also determined as complete overflow in step S4. In step S5a, the weir height h obtained by the provisional calculation from equation (8) is used. d However, the weir height h of complete overflow remains the same. d is determined by the overflow state determination unit 13. In the present invention, the term "provisional" in "provisional calculation" refers to the weir height h assuming conditions such as complete overflow or submerged overflow. d After the overflow state is judged by the overflow state judgement unit 13, the final weir height h d The value of is to be determined. (b)h / h d For H1≦3(H1≦4H2) In this case, first assume complete overflow (see Figure 2) and set the weir height h d Find h / h d The evaluation formula (empirical formula) based on the experimental results in the case of ≦3 is different from formula (7) and is the following formula (9). d It is known that when is the same, the flow coefficient shows approximately the same value when the overturning weir 22 is inclined and when it is vertical, so equation (9) also holds true when the overturning weir 22 is inclined. Equation (9) is given in Reference 3 (Hatano, Kesagi; Tadara, Kenji; Nagano, Hiroyuki; Huang, Ando: An attempt to formulate the relationship between discharge rate and overflow depth of a crenellated weir, Journal of the Japan Society of Civil Engineers, Proceedings of the JSCE, Vol. 73, No. 2, pp. 34-42, 2017).

[0038]

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[0039] H1=h d +h, the overflow depth h can be eliminated, resulting in the following equation (10). d Solving this gives us equation (11). However, the sign before the root in equation (11) is + (plus).

[0040]

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[0041]

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[0042] In addition, the dam height h d In equation (10), the upstream water depth H1 is a physical quantity that is determined when the channel flow rate Q0 is given, and is therefore stored in the database 3 in advance. c As described above, is calculated by the critical water depth calculation unit 10 for the overflow rate Q and stored in the database 3, and p and q are also stored in the database 3 in advance as various constants 16 so as to be readable via the input unit 6. Therefore, in step S3, the dam height calculation unit 12 calculates the limit water depth h c and various constants 16 are read from database 3, and the weir height h is calculated from equation (11). d Calculate provisionally:

[0043] Next, in step S4, in the collapseable weir control system 1, the overflow state determination unit 13 of the calculation unit 2 determines the provisionally calculated weir height hd and the weir height limit value h calculated in step S2 dA The weir height h in Eq. (11) is compared to determine whether the overflow is complete or submerged. d is the dam height limit h dA If the overflow is greater than 1, it is determined that there is complete overflow, and in step S5a, the collapsed weir control system 1 calculates the provisionally calculated weir height h d The overflow state determination unit 13 determines that the weir height h d is determined as:

[0044] On the other hand, the provisionally calculated dam height h d is the dam height limit h dA If it is below this, it is determined to be submerged overflow (see Figure 3), and the toppling weir control system 1 proceeds from step S4 to step S5b. In step S5b, first, the weir height calculation unit 12 solves equation (13) using the following conditional equations (12a) to (12c). Note that equation (13) is obtained by combining relational equation (9) for complete overflow and relational equation (12) for submerged overflow, and K1 to K5 in equation (13) are as shown in equations (13a) to (13e). Like equation (7), equation (9) holds for both vertical and inclined weirs. Furthermore, equations (12) to (12c) are evaluation equations (empirical equations) for experimental results of vertical weirs (Reference 4: Hatano, Kesagi, Tadara, Kenji: Hydraulic study of crested weir based on the suggestion of momentum theorem, Journal of Japan Society of Civil Engineers, Collection B1 (Hydraulic Engineering), Vol. 70, No. 1, pp. 11-21, 2014). Therefore, equation (13) can be considered to hold with a certain level of accuracy even when the overturning weir 22 is inclined. In addition, p and q included in the formulas (13a) to (13e) are the same as p and q shown in the formula (9), respectively. In addition, in equations (12a) to (12c), the downstream water level h2 and the critical water depth h c Depending on the value of the ratio, the values ​​of constants A to C are given separately for each case. These constants A to C are also stored in advance in database 3 as various constants 16 via input unit 6 so that they can be read out, and so dam height calculation unit 12 can read them out and perform calculations. Furthermore, the water depth H1 upstream of the weir is given in advance and stored in the database 3 as described above, but the water level h2 downstream of the weir and the water depth H2 downstream of the weir are h2 = H2 - h d (See Figure 3) d Since is not given, it is necessary to perform iterative calculations. In other words, the weir height h is calculated by assuming h2 to be within the range of any of the equations (12a) to (12c). d If the calculation result is within the range of the assumed h2 value, the desired dam height h d This means that we have obtained the following. Therefore, the dam height calculation unit 12 generates h2 that falls within the range of any one of the formulas (12a) to (12c), and uses this to calculate the dam height h d Calculate h2 again from the calculation result, and compare it with the initially assumed h2. If the recalculated h2 falls within the range that contains the generated h2, the weir height h calculated using the generated h2 is used. d The dam height h to be obtained d It is said that this was the case.

[0045] In addition, when the systematic experimental data of Mr. Cox of the University of Wisconsin (Reference 5: Cox, GN: The submerged weir as a measuring device, Bull. of the University of Wisconsin, 1928) was verified, the three h2 / h c h2 / h near the boundary of the interval c If we assume a downstream water level h2 corresponding to the calculated weir height h d The downstream water level h2 obtained from the weir is the adjacent h2 / h c A situation arises that belongs to the interval h2 / h c In the section, the water level downstream of the weir is newly assumed to be h2, and the weir height is h d As a result of the calculation, the weir height h d Since the calculated value was almost the same as the value calculated based on the initial assumption of the water level downstream of the weir, h2, the results of the repeated calculations are considered to be reliable. The dam height h calculated by the dam height calculation unit 12 d is the weir height h at the time of submerged overflowd Therefore, in step S5b, the overflow state determination unit 13 next determines the obtained weir height h d is determined as the weir height at the time of submerged overflow.

[0046]

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[0049] In steps S5a and S5b, the dam height h d is determined to be at the time of complete overflow or at the time of submerged overflow, in the tipping weir control system 1, the weir gradient calculation unit 14 of the calculation unit 2 calculates a target value of the weir gradient sin θ of the tipping weir 22 in step S6. Specifically, it is given by the following equation (14). sinθ=h d / L (14) Here, since the weir length L is stored in the database 3 in advance via the input unit 6, the weir gradient calculation unit 14 reads it out and calculates the weir height h determined in steps S5a and S5b. d The target value of the weir gradient sin θ can be calculated using The calculated weir gradient sin θ is stored in the database 3, and is also transmitted from the weir gradient calculation unit 14 to the weir gradient control unit 4.

[0050] Next, in step S7, the overturning dam control system 1 generates a control signal for controlling the dam tilting unit 5 based on the target value of the dam tilt sin θ received by the dam tilt control unit 4 from the dam tilt calculation unit 14, and transmits this to the dam tilting unit 5. Then, in step S8, the weir tilting unit 5 receives a control signal from the weir gradient control unit 4 and tilts the overturning weir 22 so that the weir gradient matches the target value, thereby changing the weir gradient. By controlling the tipping weir 22 to tilt in this manner, even if the channel flow rate Q0 or water intake volume Qe upstream of the tipping weir 22 changes, the target value for the weir gradient can be updated by updating the channel flow rate Q0 and water intake volume Qe in the database 3 and executing steps S1 to S7 again, and the weir gradient of the tipping weir 22 can also be controlled to be updated.

[0051] As described above, the tipping weir control system 1 according to the present embodiment employs a tipping weir 22 that can more stabilize the flow upstream and downstream of the weir in order to obtain the required water intake volume Qe from the waterway 20, and the weir height limit value h dA The distinction between complete overflow and submerged overflow is judged using the boundary value, and the evaluation formula (empirical formula) obtained based on the experimental values ​​of complete overflow and submerged overflow that have been proven in the past is applied to the weir height h d By solving the equation, the weir height h d has gained. And this dam height h d The weir gradient sin θ of the tipping weir 22 is calculated from the weir gradient calculation unit 14 of the calculation unit 2, and this is used as a target value, which is sent by the weir gradient control unit 4 obtained from the weir gradient calculation unit 14 of the calculation unit 2 to the weir tilting unit 5 as a control signal to control the gradient of the tipping weir 22, thereby enabling the necessary amount of water intake from the waterway 20 to be stably supplied to the intake channel 21. Also, unlike a gate weir, there is no outflow from the gap between the bottom of the gate and the floor of the channel, and instead water flows out from the top of the overturning weir 22 according to the overflow rate Q, so there is little significant energy loss due to contraction of the flow that occurs at a gate weir, and little erosion of the gate and floor of the channel due to the nozzle effect of the outflow water. Furthermore, the weir inclination of the overturning weir can be controlled while the overflow condition determination unit 13 determines whether the flow will be complete overflow or submerged overflow depending on the flow rate of the waterway and the amount of water taken from the waterway, making it possible to perform more precise control.

[0052] In the above explanation, the actions and effects of the tipping weir control system 1 have been explained with reference to Figures 4 and 5, but the steps explained with reference to Figure 5 can also serve as an explanation of an embodiment of a tipping weir control method, and can also serve as an embodiment of a tipping weir control program that executes these steps using a computer. The actions and effects of these tipping weir control methods and tipping weir control programs are also similar to those of the tipping weir control system 1. In this embodiment, the weir height h d Equations (8), (11), and (13) were used as the evaluation formulas for determining the weir height h d Any formula can be used as long as it can evaluate the overflow rate Q. However, it is necessary to be able to distinguish between complete overflow and submerged overflow, and to be able to determine the overflow state and adjust the weir height h according to the result of the determination. d It is necessary to be able to evaluate the weir slope and calculate it. [Industrial Applicability]

[0053] The present invention can be widely used for controlling the weir inclination of a tipping weir installed to adjust the amount of water taken from a waterway such as a river. [Explanation of symbols]

[0054] 1...Tipping weir control system 2...Calculation section 3...Database 4...Weir gradient control section 5...Weir tilting section 6...Input section 7...Output section 10...Critical water depth calculation section 11...Weir height limit calculation section 12...Weir height calculation section 13...Overflow state determination section 14...Weir gradient calculation section 15...Physical constants 16...Various constants 20...Channel 21...Intake channel 22...Tipping weir 23...Weir crest R...Overflow volume per unit width i...Channel gradient B...Channel width n...Manning's roughness coefficient h...Overflow depth h c …Limit water depth H1…Water depth upstream of weir h1…Water level upstream of weir H2…Water depth downstream of weir h2…Water level downstream of weir L…Weir length h d … Weir height θ… Weir inclination angle

Claims

1. A tipping weir control system that controls the weir inclination of a tipping weir for taking water from a waterway, comprising: a critical water depth calculation unit that calculates the critical water depth from the overflow rate of the tipping weir; a weir height calculation unit that calculates the weir height in the case of complete overflow and in the case of submerged overflow; an overflow state determination unit that determines whether complete overflow is complete or submerged overflow; a weir inclination calculation unit that calculates a target value of the weir inclination from the weir height in the case of complete overflow or submerged overflow according to the result of the determination; a weir inclination control unit that generates a control signal to control the weir inclination based on the target value; and a weir tilting unit that can change the weir inclination by the control signal generated by the weir inclination control unit.

2. The overturning weir control system according to claim 1, characterized in that it has a weir height limit value calculation unit that calculates the weir height limit value that is the limit at which submerged overflow occurs, and the overflow state determination unit uses the weir height limit value to determine whether complete overflow or submerged overflow occurs.

3. A tipping weir control method for controlling the weir inclination of a tipping weir for taking water from a waterway, comprising: a critical water depth calculation step for calculating a critical water depth from the overflow rate of the tipping weir; a provisional weir height calculation step for provisionally calculating the weir height for the cases of complete overflow and submerged overflow; an overflow state determination step for determining whether complete overflow is complete or submerged overflow; a weir height determination step for determining the weir height for complete overflow or submerged overflow in accordance with the results of the determination; a weir inclination calculation step for calculating a target value of the weir inclination from the weir height for complete overflow or submerged overflow determined in the weir height determination step; a control signal generation step for generating a control signal for the weir inclination based on the target value; and a weir tilting step for changing the weir inclination using the control signal.

4. A method for controlling a tipping dam as described in claim 3, characterized in that it includes a dam height limit value calculation process for calculating the dam height limit value which is the limit at which submerged overflow occurs, and the dam height limit value is used to determine whether complete overflow or submerged overflow occurs in the overflow state determination process.

5. A overturning weir control program executed by a computer for controlling the weir inclination of a overturning weir for taking water from a waterway, the overturning weir control program comprising the following steps: a critical water depth calculation step for calculating a critical water depth from the overflow rate of the overturning weir; a provisional weir height calculation step for provisionally calculating the weir height for the cases of complete overflow and submerged overflow; an overflow state determination step for determining whether the overflow is complete or submerged overflow; a weir height determination step for determining the weir height for complete overflow or submerged overflow based on the results of the determination; a weir inclination calculation step for calculating a target value of the weir inclination from the weir height for complete overflow or submerged overflow determined in the weir height determination step; a control signal generation step for generating a control signal for the weir inclination based on the target value; and a weir tilting step for changing the weir inclination using the control signal.

6. A collapseable weir control program as described in claim 5, characterized in that it includes a weir height limit value calculation process for calculating the weir height limit value that is the limit at which submerged overflow occurs, and the weir height limit value is used to determine whether complete overflow or submerged overflow is present in the overflow state determination process.

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