Hydraulic calculation method and device for self-pressure irrigation system

Abstract

The invention relates to the technical field of hydraulic power of a self-pressure irrigation pipe network, and discloses a hydraulic power calculation method and device of a self-pressure irrigation system. According to the method, the actual water outlet flow and the actual working pressure of the multiple water outlets of the first branch pipe and the second branch pipe and the actual working pressure of the second intersection point of the second branch pipe and the main pipe are calculated through different formulas, the optimal actual water outlet flow and the optimal actual working pressure are determined, and finally it can be guaranteed that the pressure of a pipe network is uniform; in addition, in the self-pressure irrigation system, a systematic and comprehensive pipe network hydraulic calculation mode can be provided.

Description

Technical Field

[0001] The present invention relates to the field of hydraulic technology of a self-pressure irrigation pipe network, and in particular to a hydraulic calculation method and device for a self-pressure irrigation system. Background Art

[0002] Drip irrigation is one of the most efficient and water-saving irrigation technologies in the world today. However, problems such as resource waste and energy consumption in the application of drip irrigation technology have attracted much attention. Environmental protection and energy conservation have become the themes of the development of drip irrigation technology.

[0003] my country has numerous large-scale irrigation areas in mountain-basin systems. Existing surface water canals and plain reservoirs suffer significant water losses from evaporation and seepage, and the natural topography of mountain-basin systems provides unique water and energy resources for developing pipelined water distribution and implementing self-pressurized irrigation. Therefore, constructing a large-scale self-pressurized pipelined water distribution system from the mountain piedmont to the basin can effectively address water resource utilization issues.

[0004] In the related technologies, the pressure regulation technology of the current self-pressure irrigation system is still immature, such as the pressure regulation equipment and pressure regulation technology cannot well guarantee the stable operation of large-diameter pipelines. In addition, the overall pressure of the pipeline network is uneven, and the aging performance of the pipeline is weakened, which leads to excessive pressure at local points, and ultimately easily causes the main pipe burst accident. In addition, some current research focuses on urban pipeline networks, and there is less research on agricultural self-pressure irrigation pipeline networks. Therefore, in the self-pressure irrigation system, there is a lack of systematic and comprehensive pipeline hydraulic calculation methods. Summary of the Invention

[0005] In view of this, the present invention provides a hydraulic calculation method and device for a self-pressure irrigation system to solve the problem of lack of a systematic and comprehensive pipe network hydraulic calculation method in the self-pressure irrigation system.

[0006] In a first aspect, the present invention provides a hydraulic calculation method for a self-pressure irrigation system, which is applied to the self-pressure irrigation system. The self-pressure irrigation system includes: a water source, a first branch pipe, a second branch pipe, and a main pipe, each having the same pipe diameter, wherein the first branch pipe and the second branch pipe are parallel, the main pipe is perpendicular to the first branch pipe and the second branch pipe, respectively, multiple water outlets of the same diameter and height are arranged at preset intervals on the first branch pipe and the second branch pipe, a first solenoid valve is provided at a first intersection of the main pipe and the first branch pipe, and a second solenoid valve is provided at a second intersection of the main pipe and the second branch pipe, and water flows from the water source into the main pipe, the first branch pipe, and the second branch pipe. The method includes:

[0007] Based on the preset range of values, the initial working pressures of the end water outlets of the first branch pipe and the second branch pipe are set respectively;

[0008] Based on the hydraulic calculation parameters and initial working pressure of the branch pipe, the actual water flow rate and actual working pressure of the terminal water outlets of the first branch pipe and the second branch pipe are calculated respectively using the first hydraulic calculation formula;

[0009] Based on the hydraulic calculation parameters of the branch pipe, the actual water flow rate and actual working pressure of the first outlet adjacent to the terminal outlet of the first branch pipe and the second branch pipe are calculated respectively using the second hydraulic calculation formula;

[0010] The actual water flow rate and the actual working pressure of the plurality of water outlets between the first water outlet of the first branch pipe and the first solenoid valve and between the first water outlet of the second branch pipe and the second solenoid valve are calculated step by step in a recursive manner using the second hydraulic calculation formula;

[0011] Based on the hydraulic calculation parameters of the branch pipe, the actual working pressure at the second intersection of the second branch pipe and the main pipe is calculated using the third hydraulic calculation formula;

[0012] Based on the hydraulic calculation parameters of the branch pipe, the target working pressure at the second intersection of the first branch pipe and the main pipe is calculated using the fourth hydraulic calculation formula;

[0013] If the absolute value of the difference between the actual working pressure and the target working pressure is greater than a first preset threshold, returning to the step of setting the initial working pressures of the end water outlets of the first branch pipe and the second branch pipe respectively based on the preset range of values;

[0014] If the absolute value of the difference between the actual working pressure and the target working pressure is less than or equal to the first preset threshold, the total gravitational potential energy of the main pipe is calculated using the fifth and sixth calculation formulas based on the hydraulic calculation parameters of the main pipe and the hydraulic calculation parameters of the branch pipe;

[0015] If the absolute value of the difference between the actual gravitational potential energy and the total gravitational potential energy between the water source and the head end inlet of the main pipe is less than or equal to a second preset threshold, the actual water flow rate and the actual working pressure of the multiple water outlets of the first branch pipe and the second branch pipe are output one by one;

[0016] If the absolute value of the difference between the actual gravitational potential energy and the total gravitational potential energy between the water source and the head end inlet of the main pipe is greater than the second preset threshold, return to the step of setting the initial working pressure of the end water outlet of the first branch pipe and the second branch pipe respectively based on the preset range value.

[0017] The embodiment of the present disclosure calculates the actual water flow rate and actual working pressure of multiple water outlets of the first branch pipe and the second branch pipe, as well as the actual working pressure at the second intersection of the second branch pipe and the main pipe through different formulas by executing the above method, and determines the optimal actual water flow rate and actual working pressure. Ultimately, the present invention can ensure uniform pressure in the pipe network, prevent pipeline explosion accidents, and provide a systematic and comprehensive pipe network hydraulic calculation method in the self-pressure irrigation system.

[0018] In some optional implementations, the actual water flow rate and actual working pressure of the terminal water outlet of the first branch pipe are calculated using the following first hydraulic calculation formula;

[0019]

[0020] Q u (a,n a )=Q s (a,n a )

[0021]

[0022]

[0023] Among them, Q s (a,n a ) is the outlet n at the end of branch pipe a a The actual water flow rate, μ is the outlet flow coefficient of branch a, A s The outlet n at the end of branch pipe a a The cross-sectional area of ​​water flow, H s (a,n a ) is the outlet n at the end of branch pipe a a Initial working pressure, Q u (a,n a ) is the outlet n at the end of branch pipe a a The flow rate of the upstream branch pipe section, H u (a,n a ) is the outlet n at the end of branch pipe a a Upstream section working pressure, V s (a,n a ) End outlet n of branch pipe a a The average outlet velocity, g is the acceleration of gravity, f is the pipe friction coefficient, L s is the vertical pipe length of branch a, m is the flow index, D S is the inner diameter of the vertical pipe of branch a, ζ1 is the local resistance coefficient of the reducing right-angle elbow, b is the pipe diameter index, V u (a,n a ) is the outlet n at the end of branch pipe aa The average inlet flow rate.

[0024] By executing the above-mentioned implementation manner, the embodiment of the present disclosure can accurately calculate the actual water flow rate and actual working pressure of the terminal water outlets of the first branch pipe and the second branch pipe through the first hydraulic calculation formula.

[0025] In some optional embodiments, the actual water flow rate and the actual working pressure of the first water outlet adjacent to the terminal water outlet of the first branch pipe and the second branch pipe are calculated respectively by the following second hydraulic calculation formula;

[0026]

[0027]

[0028] V u (a,n a )=Q u (a,n a ) / A z

[0029] V s (a,n a-1 )=Q s (a,n a-1 ) / A s

[0030]

[0031]

[0032] Q u (a,n a-1 )=Q s (a,n a-1 )+Q u (a,n a )

[0033] Among them, H d (a,n a-1 ) is the first outlet n of branch pipe a a-1 Downstream section working pressure, H u (a,n a ) is the outlet n at the end of branch pipe a a The upstream section working pressure, f is the pipeline friction coefficient, Q u (a,n a ) is the outlet n at the end of branch pipe a a The flow rate of the upstream branch pipe section, L z is the length of the branch pipe section between two adjacent outlets of branch pipe a, b is the pipe diameter index, D z is the inner diameter of branch pipe a, Zs (a,n a ) is the height difference between the two ends of the branch pipe section between adjacent outlets, H u (a,n a-1 ) is the first outlet n of branch pipe a a-1 The upstream section working pressure, ζ2 is the local resistance coefficient of the DC tee of branch pipe a, V u (a,n a ) is the outlet n at the end of branch pipe a a The average inlet velocity, g is the acceleration of gravity, A z is the water flow cross-sectional area of ​​branch pipe a, V s (a,n a-1 ) is the first outlet n of branch pipe a a-1 The average outlet velocity, A s The outlet n at the end of branch pipe a a The cross-sectional area of ​​water flow, Q s (a,n a-1 ) is the first outlet n of branch pipe a a-1 The actual water flow rate, μ is the outlet flow coefficient of the branch pipe, H s (a,n a-1 ) is the first outlet n of branch pipe a a-1 The actual working pressure, D S L is the inner diameter of the vertical pipe of branch a, s is the vertical pipe length of branch a, ζ3 is the local resistance coefficient of the baffle tee of branch a, Q u (a,n a-1 ) is the first outlet n of branch pipe a a-1 The flow rate of the upstream branch pipe section.

[0034] By executing the above-mentioned implementation manner, the embodiment of the present disclosure can accurately calculate the actual water flow rate and actual working pressure of the first water outlet adjacent to the end water outlet of the first branch pipe and the second branch pipe through the second hydraulic calculation formula.

[0035] In some optional embodiments, the actual water flow rate and the actual working pressure at the second intersection of the second branch pipe and the main pipe are calculated using a third hydraulic calculation formula;

[0036]

[0037] Q z (c) = Q u (c,1)

[0038]

[0039] Among them, H u(c,1) is the working pressure of the upstream section of the outlet of the first end of the second branch pipe, f is the friction coefficient of the pipe, Q u (c,1) is the flow rate of the upstream section of the outlet of the first end of the second branch pipe, m is the flow index, L c D is the horizontal distance from the outlet of the second branch pipe to the main pipe. z is the inner diameter of the branch pipe, Z c0 is the height difference between the outlet of the first end of the second branch pipe and the main pipe, ζ4 is the local resistance coefficient of the valve at the first end of the branch pipe, V u (c,1) is the average inlet velocity of the first outlet of the second branch, g is the acceleration of gravity, Q z (c) is the total water flow rate at the second solenoid valve, H u (g) is the actual working pressure at the second intersection of the second branch pipe and the main pipe, H z (c) is the total working pressure at the second solenoid valve, ζ6 is the local resistance coefficient of the diverting three-way valve at the second branch pipe, V z (c) is the average flow rate at the second solenoid valve.

[0040] By executing the above-mentioned implementation method, the embodiment of the present disclosure can accurately calculate the actual water flow rate and actual working pressure at the second intersection of the second branch pipe and the main pipe through the third hydraulic calculation formula.

[0041] In some optional embodiments, the target water flow rate and target working pressure at the second intersection of the first branch pipe and the main pipe are calculated using the following fourth hydraulic calculation formula;

[0042]

[0043] Q z (a) = Q u (a,1)

[0044]

[0045] Q g (a) = Q z (a)

[0046] again Substituting in:

[0047]

[0048] Among them, H u (a,1) is the working pressure of the upstream section of the outlet of the first branch pipe, f is the friction coefficient of the pipe, Q u (a,1) is the flow rate of the upstream section of the outlet of the first branch pipe, m is the flow index, L a D is the horizontal distance from the outlet of the first branch pipe to the main pipe.z is the inner diameter of the branch pipe, Z a0 is the height difference between the outlet of the first branch pipe and the main pipe, ζ4 is the local resistance coefficient of the valve at the head end of the branch pipe, V u (a,1) is the average inlet velocity of the first branch outlet, g is the acceleration of gravity, Q z (a) is the total water flow rate at the first solenoid valve, H d (g) is the intermediate parameter, H z (a) is the total working pressure at the first solenoid valve, Q g (a) is the total outflow rate at the first branch, L g is the distance between the first and second intersection points, D g is the inner diameter of the main pipe, b is the pipe diameter index, Z0 is the height difference between the first and second intersection points of the main pipe, ζ5 is the sum of the local resistance coefficients of the DC tees on the main pipe between the first and second intersection points, V z (a) is the average flow velocity at the first solenoid valve, V z (c) is the average flow velocity at the second solenoid valve, ζ7 is the local resistance coefficient of the DC tee at the second branch pipe, H u '(g) is the target working pressure at the second intersection of the first branch pipe and the main pipe.

[0049] By executing the above-mentioned implementation method, the embodiment of the present disclosure can accurately calculate the target water outlet flow rate and target working pressure at the second intersection of the first branch pipe and the main pipe through the fourth hydraulic calculation formula.

[0050] In some optional implementations, the total gravitational potential energy of the main pipe is calculated using the following fifth and sixth calculation formulas:

[0051] When there is an intersection between the second branch pipe and the main pipe inlet, the total gravitational potential energy of the main pipe is calculated using the following fifth calculation formula;

[0052] Q g =Q z (a)+Q z (c)

[0053]

[0054] When there is no intersection between the second branch pipe and the main pipe inlet, the total gravitational potential energy of the main pipe is calculated using the following sixth calculation formula:

[0055] Q g =Q z (a)+Q z (c)

[0056]

[0057]

[0058] Among them, Q g is the total outflow of the main pipe, Q z (a) is the total water flow rate at the first solenoid valve, Q z (c) is the total water flow rate at the second solenoid valve, Z g ′ is the total gravitational potential energy of the main pipe, H u (g) is the actual working pressure at the second intersection of the second branch pipe and the main pipe, f is the pipeline friction coefficient, m is the flow index, L gs D is the length of the pipe section between the water source and the main pipe inlet, gs is the inner diameter of the pipe between the water source and the main pipe inlet, b is the pipe diameter index, ζ8 is the local resistance coefficient of the main pipe head valve, V g is the average flow velocity of the main pipe, g is the acceleration of gravity, L0 is the length of the pipe section between the second branch pipe and the main pipe inlet, Z1 is the height difference between the second branch pipe and the main pipe inlet, and ζ9 is the sum of the local resistance coefficients of each DC three-way valve at the main pipe inlet.

[0059] By executing the above-mentioned implementation manner, the embodiment of the present disclosure can accurately calculate the total gravitational potential energy of the main pipe using the fifth calculation formula and the sixth calculation formula.

[0060] In a second aspect, the present invention provides a hydraulic calculation device for a self-pressure irrigation system, which is applied to the self-pressure irrigation system. The self-pressure irrigation system includes: a water source, a first branch pipe, a second branch pipe, and a main pipe, each having the same pipe diameter, wherein the first branch pipe and the second branch pipe are parallel, the main pipe is perpendicular to the first branch pipe and the second branch pipe, respectively, multiple water outlets of the same diameter and height are arranged at preset intervals on the first branch pipe and the second branch pipe, a first solenoid valve is provided at a first intersection of the main pipe and the first branch pipe, and a second solenoid valve is provided at a second intersection of the main pipe and the second branch pipe, and water flows from the water source into the main pipe, the first branch pipe, and the second branch pipe. The device includes:

[0061] A parameter setting module, for setting the initial working pressures of the end water outlets of the first branch pipe and the second branch pipe respectively based on a preset range of values;

[0062] A first calculation module is used to calculate the actual water flow rate and actual working pressure of the terminal water outlets of the first branch pipe and the second branch pipe respectively based on the branch pipe hydraulic calculation parameters and the initial working pressure using a first hydraulic calculation formula;

[0063] A second calculation module is used to calculate the actual water flow rate and actual working pressure of the first water outlet adjacent to the terminal water outlet of the first branch pipe and the second branch pipe respectively based on the branch pipe hydraulic calculation parameters and using a second hydraulic calculation formula;

[0064] a third calculation module, configured to recursively calculate, using the second hydraulic calculation formula, the actual water flow rates and actual working pressures of the plurality of water outlets between the first water outlet of the first branch pipe and the first solenoid valve and between the first water outlet of the second branch pipe and the second solenoid valve;

[0065] a fourth calculation module, configured to calculate the actual working pressure at the second intersection of the second branch pipe and the main pipe based on the branch pipe hydraulic calculation parameters and using the third hydraulic calculation formula;

[0066] a fifth calculation module, configured to calculate a target operating pressure at a second intersection of the first branch pipe and the main pipe using a fourth hydraulic calculation formula based on the branch pipe hydraulic calculation parameters;

[0067] a first optimization module, configured to return a value based on a preset range to set the initial working pressures of the end water outlets of the first branch pipe and the second branch pipe, respectively, if the absolute value of the difference between the actual working pressure and the target working pressure is greater than a first preset threshold;

[0068] a sixth calculation module, configured to calculate the total gravitational potential energy of the main pipe using the fifth and sixth calculation formulas based on the main pipe hydraulic calculation parameters and the branch pipe hydraulic calculation parameters if the absolute value of the difference between the actual working pressure and the target working pressure is less than or equal to the first preset threshold;

[0069] a parameter output module, configured to output the actual water flow rates and actual working pressures of the plurality of water outlets of the first branch pipe and the second branch pipe one by one if the absolute value of the difference between the actual gravitational potential energy and the total gravitational potential energy between the water source and the head end inlet of the main pipe is less than or equal to a second preset threshold;

[0070] The second optimization module is used to return to the module to set the initial working pressure of the end water outlet of the first branch pipe and the second branch pipe respectively based on the preset range value if the absolute value of the difference between the actual gravitational potential energy and the total gravitational potential energy between the water source and the head end inlet of the main pipe is greater than the second preset threshold.

[0071] In a third aspect, the present invention provides a computer device comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the computer instructions to thereby execute the hydraulic calculation method for the self-pressure irrigation system of the first aspect or any corresponding embodiment thereof.

[0072] In a fourth aspect, the present invention provides a computer-readable storage medium having computer instructions stored thereon, the computer instructions being used to enable a computer to execute the hydraulic calculation method for a self-pressure irrigation system according to the first aspect or any corresponding embodiment thereof.

[0073] In a fifth aspect, the present invention provides a computer program product, characterized in that it includes computer instructions, and the computer instructions are used to enable a computer to execute the hydraulic calculation method of the self-pressure irrigation system of the above-mentioned first aspect or any corresponding embodiment thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0074] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0075] Figure 1 is a schematic diagram of a pipe network of a self-pressure irrigation system according to an embodiment of the present invention;

[0076] Figure 2 is a flow chart of a hydraulic calculation method for a self-pressure irrigation system according to an embodiment of the present invention;

[0077] Figure 3 is a schematic diagram of a pipe network of a self-pressure irrigation system according to an embodiment of the present invention;

[0078] Figure 4 is a schematic diagram of a pipe network of another self-pressure irrigation system according to an embodiment of the present invention;

[0079] Figure 5 is a structural block diagram of a hydraulic calculation device for a self-pressure irrigation system according to an embodiment of the present invention;

[0080] Figure 6 Schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0081] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present invention.

[0082] According to an embodiment of the present invention, a self-pressure irrigation system is provided. Figure 1 As shown, the self-pressure irrigation system includes: a water source 10, a first branch pipe 11, a second branch pipe 12 and a main pipe 13 with the same pipe diameter, wherein the first branch pipe 11 and the second branch pipe 12 are parallel, the main pipe 13 is perpendicular to the first branch pipe 11 and the second branch pipe 12 respectively, and multiple water outlets (n) with the same diameter and height are arranged on the first branch pipe 11 and the second branch pipe 12 at preset intervals. a 、n a-1 、…n a-n ), a first solenoid valve 14 is set at the first intersection D of the main pipe 13 and the first branch pipe 11, and a second solenoid valve 15 is set at the second intersection E of the main pipe 13 and the second branch pipe 12, and water flows from the water source 10 into the main pipe 13, the first branch pipe 11 and the second branch pipe 12.

[0083] Specifically, the water source can be a reservoir or a river. Figure 1 In the embodiment, a first branch pipe 11, a second branch pipe 12, a main pipe 13, a first solenoid valve 14, and a second solenoid valve 15 are selected to form a self-pressure irrigation system. Multiple water outlets of the same diameter and height are arranged at predetermined intervals on the first branch pipe 11 and the second branch pipe 12. The self-pressure irrigation system of the disclosed embodiment is further calculated to prevent uneven pressure in the overall pipe network and the resulting weakening of pipe performance due to aging, which can lead to excessive pressure at local points and ultimately cause main pipe bursts.

[0084] According to an embodiment of the present invention, an embodiment of the present disclosure provides an embodiment of a hydraulic calculation method for a self-pressure irrigation system. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0085] In this embodiment, a hydraulic calculation method for a self-pressure irrigation system is provided, which can be used on mobile terminals such as mobile phones and tablet computers. Figure 2 FIG. 1 is a flow chart of a hydraulic calculation method for a self-pressure irrigation system according to an embodiment of the present invention. Figure 2 As shown, the process includes the following steps:

[0086] Step S201 : setting the initial working pressures of the terminal water outlets of the first branch pipe and the second branch pipe respectively based on a preset range of values.

[0087] Specifically, the preset range value is the end water outlet n of the first branch pipe and the second branch pipe. a The reasonable range of the initial working pressure is (h1, h2), let H s (a,n a)=(h1+h2) / 2,H s The end outlet n of the first and second branch pipes a The initial working pressure and the preset range value can be flexibly set according to the actual application scenario.

[0088] Step S202 , based on the branch pipe hydraulic calculation parameters and the initial working pressure, the actual water flow rate and the actual working pressure of the terminal water outlets of the first branch pipe and the second branch pipe are calculated respectively by a first hydraulic calculation formula.

[0089] Specifically, the branch pipe hydraulic calculation parameters are hydraulic calculation parameters related to the first branch pipe or the second branch pipe, such as Figure 3 As shown, the outlet n at the end of branch pipe a a The actual water flow rate Q s (a,n a ) and actual working pressure H s (a,n a ), branch pipe a here includes a first branch pipe and a second branch pipe.

[0090] In a specific example, the first hydraulic calculation formula is expressed as follows:

[0091]

[0092] Q u (a,n a )=Q s (a,n a )

[0093]

[0094]

[0095] Among them, Q s (a,n a ) is the outlet n at the end of branch pipe a a The actual water flow rate, μ is the outlet flow coefficient of branch a, A s The outlet n at the end of branch pipe a a The cross-sectional area of ​​water flow, H s (a,n a ) is the outlet n at the end of branch pipe a a Initial working pressure, Q u (a,n a ) is the outlet n at the end of branch pipe a a The flow rate of the upstream branch pipe section, H u (a,n a ) is the outlet n at the end of branch pipe a a Upstream section working pressure, V s(a,n a ) End outlet n of branch pipe a a The average outlet velocity, g is the acceleration of gravity, f is the pipe friction coefficient, L s is the vertical pipe length of branch a, m is the flow index, D S is the inner diameter of the vertical pipe of branch a, ζ1 is the local resistance coefficient of the reducing right-angle elbow, b is the pipe diameter index, V u (a,n a ) is the outlet n at the end of branch pipe a a The average inlet flow rate.

[0096] In the above formula, the actual water flow rate Q is removed s (a,n a ) and actual working pressure H s (a,n a ), and the remaining parameters belong to branch pipe hydraulic calculation parameters.

[0097] Step S203 , based on the branch pipe hydraulic calculation parameters, the actual water flow rate and actual working pressure of the first water outlet adjacent to the terminal water outlet of the first branch pipe and the second branch pipe are calculated respectively by a second hydraulic calculation formula.

[0098] Specifically, in Figure 3 In the example, the first outlet adjacent to the terminal outlet a is n. a-1 , first water outlet n a-1 The actual water flow rate Q s (a,n a-1 ) and actual working pressure H s (a,n a-1 ).

[0099] In a specific example, the second hydraulic calculation formula is expressed as follows:

[0100]

[0101]

[0102] V u (a,n a )=Q u (a,n a ) / A z

[0103] V s (a,n a-1 )=Q s (a,n a-1 ) / A s

[0104]

[0105]

[0106] Q u (a,n a-1 )=Q s (a,n a-1 )+Q u (a,n a )

[0107] Among them, H d (a,n a-1 ) is the first outlet n of branch pipe a a-1 Downstream section working pressure, H u (a,n a ) is the outlet n at the end of branch pipe a a The upstream section working pressure, f is the pipeline friction coefficient, Q u (a,n a ) is the outlet n at the end of branch pipe a a The flow rate of the upstream branch pipe section, L z is the length of the branch pipe section between two adjacent outlets of branch pipe a, b is the pipe diameter index, D z is the inner diameter of branch pipe a, Z s (a,n a ) is the height difference between the two ends of the branch pipe section between adjacent outlets, H u (a,n a-1 ) is the first outlet n of branch pipe a a-1 The upstream section working pressure, ζ2 is the local resistance coefficient of the DC tee of branch pipe a, V u (a,n a ) is the outlet n at the end of branch pipe a a The average inlet velocity, g is the acceleration of gravity, A z is the water flow cross-sectional area of ​​branch pipe a, V s (a,n a-1 ) is the first outlet n of branch pipe a a-1 The average outlet velocity, A s The outlet n at the end of branch pipe a a The cross-sectional area of ​​water flow, Q s (a,n a-1 ) is the first outlet n of branch pipe a a-1 The actual water flow rate, μ is the outlet flow coefficient of the branch pipe, H s (a,n a-1 ) is the first outlet n of branch pipe a a-1 The actual working pressure, D S L is the inner diameter of the vertical pipe of branch a, s is the vertical pipe length of branch a, ζ3 is the local resistance coefficient of the baffle tee of branch a, Qu (a,n a-1 ) is the first outlet n of branch pipe a a-1 The flow rate of the upstream branch pipe section.

[0108] In the above formula, remove the first outlet n a-1 The actual water flow rate Q s (a,n a-1 ) and actual working pressure H s (a,n a-1 ), and the remaining parameters belong to branch pipe hydraulic calculation parameters.

[0109] In step S204, the actual water flow rate and actual working pressure of multiple water outlets between the first water outlet of the first branch pipe and the first solenoid valve and between the first water outlet of the second branch pipe and the second solenoid valve are calculated step by step in a recursive manner using the second hydraulic calculation formula.

[0110] Specifically, in Figure 1 In the process, since there are multiple water outlets between the first water outlet of the first branch pipe and the first solenoid valve and between the first water outlet of the second branch pipe and the second solenoid valve, the actual water flow rate and actual working pressure of the front-stage water outlet are used as input parameters of the rear-stage water outlet. Figure 1 The final outlet is the rear outlet n a , the front stage outlet is n a-1 According to the second formula above, the actual water flow rate and actual working pressure of multiple water outlets between the first water outlet of the first branch pipe and the first solenoid valve and the first water outlet of the second branch pipe and the second solenoid valve are calculated step by step.

[0111] Exemplarily, a recursive method is used to calculate based on the first hydraulic calculation parameter of the first branch pipe and the calculation result of the terminal water outlet. The second hydraulic calculation formula is used as the calling formula. The second hydraulic calculation formula is repeatedly called by a for loop in the Python environment. Each time the second hydraulic calculation formula is called, the variable is initialized, that is, the input value of the latter water outlet is the calculated value of the former water outlet. The call is repeated until the first water outlet of the first branch pipe is calculated. Finally, the H and Q of all water outlets of the first branch pipe except the terminal water outlet can be obtained, and the calculation results are saved.

[0112] Step S205 : Based on the hydraulic calculation parameters of the branch pipe, the actual working pressure at the second intersection of the second branch pipe and the main pipe is calculated using a third hydraulic calculation formula.

[0113] Specifically, in Figure 1 The actual working pressure at the second intersection E of the second branch pipe 12 and the main pipe 13 is H u (g). Figure 4As shown, the first end water outlet of the first branch pipe and the first end water outlet of the second branch pipe are shown. Figure 4 In the figure, branch a is the first branch, branch c is the second branch, and L gs is the length of the pipe section from the second branch to the water source, L a L is the horizontal distance from the outlet point of the first branch pipe to the main pipe. g is the distance between the first intersection point D and the second intersection point E, L c It is the distance between the first intersection point E and the water outlet at the first end of the second branch pipe.

[0114] In a specific example, the actual working pressure at the second intersection of the second branch pipe and the main pipe is calculated using the following third hydraulic calculation formula;

[0115]

[0116] Q z (c) = Q u (c,1)

[0117]

[0118] Among them, H u (c,1) is the working pressure of the upstream section of the outlet of the first end of the second branch pipe, f is the friction coefficient of the pipe, Q u (c,1) is the flow rate of the upstream section of the outlet of the first end of the second branch pipe, m is the flow index, L c D is the horizontal distance from the outlet of the second branch pipe to the main pipe. z is the inner diameter of the branch pipe, Z c0 is the height difference between the outlet of the first end of the second branch pipe and the main pipe, ζ4 is the local resistance coefficient of the valve at the first end of the branch pipe, V u (c,1) is the average inlet velocity of the first outlet of the second branch, g is the acceleration of gravity, Q z (c) is the total water flow rate at the second solenoid valve, H u (g) is the actual working pressure at the second intersection of the second branch pipe and the main pipe, H z (c) is the total working pressure at the second solenoid valve, ζ6 is the local resistance coefficient of the diverting three-way valve at the second branch pipe, V z (c) is the average flow rate at the second solenoid valve.

[0119] In the above formula, except for the actual working pressure H at the second intersection of the second branch pipe and the main pipe u Except for (g), the remaining parameters belong to branch pipe hydraulic calculation parameters.

[0120] Step S206: Calculate the target working pressure at the second intersection of the first branch pipe and the main pipe using the fourth hydraulic calculation formula based on the branch pipe hydraulic calculation parameters.

[0121] Specifically, in Figure 1 The actual working pressure at the second intersection E of the second branch pipe 12 and the main pipe 13 is H u ′(g). Figure 4 In the figure, the water outlet at the first end of the first branch pipe and the water outlet at the first end of the second branch pipe are shown. gs is the length of the pipe section from the second branch to the water source, L a L is the horizontal distance from the outlet point of the first branch pipe to the main pipe. g is the distance between the first intersection point D and the second intersection point E, L c It is the distance between the first intersection E and the outlet of the first end of the second branch pipe c.

[0122] In a specific example, the target water flow rate and target working pressure at the second intersection of the first branch pipe and the main pipe are calculated using the following fourth hydraulic calculation formula;

[0123]

[0124] Q z (a) = Q u (a,1)

[0125]

[0126] Q g (a) = Q z (a)

[0127] again Substituting in:

[0128]

[0129] Among them, H u (a,1) is the working pressure of the upstream section of the outlet of the first branch pipe, f is the friction coefficient of the pipe, Q u (a,1) is the flow rate of the upstream section of the outlet of the first branch pipe, m is the flow index, L a D is the horizontal distance from the outlet of the first branch pipe to the main pipe. z is the inner diameter of the branch pipe, Z a0 is the height difference between the outlet of the first branch pipe and the main pipe, ζ4 is the local resistance coefficient of the valve at the head end of the branch pipe, V u (a,1) is the average inlet velocity of the first branch outlet, g is the acceleration of gravity, Q z (a) is the total water flow rate at the first solenoid valve, H d(g) is the intermediate parameter, H z (a) is the total working pressure at the first solenoid valve, Q g (a) is the total outflow rate at the first branch, L g is the distance between the first and second intersection points, D g is the inner diameter of the main pipe, b is the pipe diameter index, Z0 is the height difference between the first and second intersection points of the main pipe, ζ5 is the sum of the local resistance coefficients of the DC tees on the main pipe between the first and second intersection points, V z (a) is the average flow velocity at the first solenoid valve, V z (c) is the average flow velocity at the second solenoid valve, ζ7 is the local resistance coefficient of the DC tee at the second branch pipe, H u '(g) is the target working pressure at the second intersection of the first branch pipe and the main pipe.

[0130] In the above formula, the target working pressure H is removed u Except for ′(g), the rest of the parameters belong to the hydraulic calculation parameters of the branch pipe.

[0131] Step S207: If the absolute value of the difference between the actual working pressure and the target working pressure is greater than the first preset threshold, return to the step of setting the initial working pressures of the end water outlets of the first branch pipe and the second branch pipe based on the preset range of values.

[0132] Specifically, the actual working pressure is H u (g), target working pressure H u '(g), the first preset threshold is E1, further judgment |H u (g)-H u '(g)|≦E1=0.01, the first preset threshold E1 can be flexibly set in combination with the actual scenario. u (g)-H u '(g)|>E1=0.01, then return to step S201 of setting the initial working pressure of the end outlet of the first branch pipe based on the preset range value. If |H u (g)-H u If ′(g)|≦E1=0.01, the next step of calculation is entered; otherwise, the optimization principle is used to return to step S201 and the calculation is cyclical.

[0133] Step S208: If the absolute value of the difference between the actual working pressure and the target working pressure is less than or equal to the first preset threshold, the total gravitational potential energy of the main pipe is calculated based on the hydraulic calculation parameters of the main pipe and the hydraulic calculation parameters of the branch pipe using the fifth calculation formula and the sixth calculation formula.

[0134] Specifically, if |H u (g)-Hu ′(g)|≦E1=0.01, calculate the total gravitational potential energy Z of the main pipe g ′.

[0135] In a specific example, the total gravitational potential energy of the main pipe is calculated using the following fifth and sixth calculation formulas.

[0136] When there is an intersection between the second branch pipe and the main pipe inlet, the total gravitational potential energy of the main pipe is calculated using the following fifth calculation formula;

[0137] Q g =Q z (a)+Q z (c)

[0138]

[0139] When there is no intersection between the second branch pipe and the main pipe inlet, the total gravitational potential energy of the main pipe is calculated using the following sixth calculation formula:

[0140] Q g =Q z (a)+Q z (c)

[0141]

[0142]

[0143] Among them, Q g is the total outflow of the main pipe, Q z (a) is the total water flow rate at the first solenoid valve, Q z (c) is the total water flow rate at the second solenoid valve, Z g ′ is the total gravitational potential energy of the main pipe, H u (g) is the actual working pressure at the second intersection of the second branch pipe and the main pipe, f is the pipeline friction coefficient, m is the flow index, L gs D is the length of the pipe section between the water source and the main pipe inlet, gs is the inner diameter of the pipe between the water source and the main pipe inlet, b is the pipe diameter index, ζ8 is the local resistance coefficient of the main pipe head valve, V g is the average flow velocity of the main pipe, g is the acceleration of gravity, L0 is the length of the pipe section between the second branch pipe and the main pipe inlet, Z1 is the height difference between the second branch pipe and the main pipe inlet, and ζ9 is the sum of the local resistance coefficients of each DC three-way valve at the main pipe inlet.

[0144] Among the above parameters, the parameter associated with the first branch pipe is the first hydraulic calculation parameter of the first branch pipe, the parameter associated with the second branch pipe is the second hydraulic calculation parameter of the second branch pipe, and the parameter associated with the main pipe is the third hydraulic calculation parameter of the main pipe.

[0145] Step S209: If the absolute value of the difference between the actual gravitational potential energy and the total gravitational potential energy between the water source and the head end inlet of the main pipe is less than or equal to the second preset threshold, the actual water flow rate and actual working pressure of multiple water outlets of the first branch pipe and the second branch pipe are output one by one.

[0146] Step S210: If the absolute value of the difference between the actual gravitational potential energy and the total gravitational potential energy between the water source and the head end inlet of the main pipe is greater than the second preset threshold, return to the step of setting the initial working pressure of the end water outlet of the first branch pipe based on the preset range value.

[0147] Specifically, the actual gravitational potential energy is Z g , total gravitational potential energy Z g ', the second preset threshold is E2, and the second preset threshold can be flexibly applied in combination with actual application scenarios.

[0148] Specifically, the trunk pipe connecting the reservoir and the irrigation area is used as the carrier, and the total output potential energy Z of the trunk pipe section is calculated by the fifth and sixth calculation formulas above. g ', self-pressure irrigation technology uses the natural height difference of the terrain to convert the gravitational potential energy accumulated in the pipeline into the working pressure head required for irrigation. Using this feature, the total gravitational potential energy Z of the calculated main pipeline section is converted into g ′ and the accumulated actual gravitational potential energy Z g Compare and determine whether the difference between the two meets the requirements of |Z g -Z g ′|≦E2=0.01, if it meets the accuracy requirement, the actual working pressure and actual water flow rate of all the outlets of the first branch and the second branch will be output one by one. If it does not meet the accuracy requirement, that is, |Z g -Z g When ′|﹥E2=0.01, the optimization principle is used to narrow the pressure value range, and the appropriate initial working pressure is selected for cyclic calculation until the accuracy requirement is met and the result is output.

[0149] This embodiment also provides a hydraulic calculation device for a self-pressure irrigation system. This device is used to implement the above-mentioned embodiments and preferred implementations, and details already described will not be repeated. As used below, the term "module" may refer to a combination of software and / or hardware that implements a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, implementation using hardware, or a combination of software and hardware, is also possible and contemplated.

[0150] This embodiment provides a hydraulic calculation device for a self-pressure irrigation system. Figure 5 As shown, including:

[0151] The parameter setting module 51 is used to set the initial working pressure of the terminal water outlets of the first branch pipe and the second branch pipe respectively based on the preset range of values;

[0152] A first calculation module 52 is configured to calculate the actual water flow rate and the actual working pressure of the terminal outlets of the first branch pipe and the second branch pipe respectively based on the branch pipe hydraulic calculation parameters and the initial working pressure using a first hydraulic calculation formula;

[0153] The second calculation module 53 is used to calculate the actual water flow rate and actual working pressure of the first outlet adjacent to the terminal outlet of the first branch pipe and the second branch pipe respectively based on the branch pipe hydraulic calculation parameters and using the second hydraulic calculation formula;

[0154] a third calculation module 54 for recursively calculating, using a second hydraulic calculation formula, the actual water flow rates and actual working pressures of the plurality of water outlets between the first water outlet of the first branch pipe and the first solenoid valve and between the first water outlet of the second branch pipe and the second solenoid valve;

[0155] A fourth calculation module 55 is configured to calculate the actual working pressure at the second intersection of the second branch pipe and the main pipe based on the branch pipe hydraulic calculation parameters and using a third hydraulic calculation formula;

[0156] a fifth calculation module 56 for calculating a target operating pressure at a second intersection of the first branch pipe and the main pipe based on the branch pipe hydraulic calculation parameters and using a fourth hydraulic calculation formula;

[0157] A first optimization module 57 is configured to return a value based on a preset range to set the initial working pressures of the end water outlets of the first branch pipe and the second branch pipe, respectively, if the absolute value of the difference between the actual working pressure and the target working pressure is greater than a first preset threshold;

[0158] a sixth calculation module 58 configured to calculate the total gravitational potential energy of the main pipe using the fifth and sixth calculation formulas based on the main pipe hydraulic calculation parameters and the branch pipe hydraulic calculation parameters if the absolute value of the difference between the actual working pressure and the target working pressure is less than or equal to the first preset threshold;

[0159] a parameter output module 59 for outputting the actual water flow rates and actual working pressures of the plurality of water outlets of the first branch pipe and the second branch pipe one by one if the absolute value of the difference between the actual gravitational potential energy and the total gravitational potential energy between the water source and the head end inlet of the main pipe is less than or equal to a second preset threshold;

[0160] A second optimization module 60 is configured to return to the module for setting the initial operating pressures of the terminal water outlets of the first and second branch pipes based on a preset range of values ​​if the absolute value of the difference between the actual gravitational potential energy and the total gravitational potential energy between the water source and the head end inlet of the main pipe is greater than a second preset threshold.

[0161] The further functional description of each of the above modules and units is the same as that of the above corresponding embodiments and will not be repeated here.

[0162] The hydraulic calculation device of the self-pressure irrigation system in this embodiment is presented in the form of a functional unit, where the unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and memory that executes one or more software or fixed programs, and / or other devices that can provide the above functions.

[0163] An embodiment of the present invention further provides a computer device having the hydraulic calculation device of the self-pressure irrigation system described above.

[0164] See also Figure 6 , Figure 6 is a structural diagram of a computer device provided by an optional embodiment of the present invention, such as Figure 6 As shown, the computer device includes: one or more processors 10, memory 20, and interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. Various components utilize different buses to communicate with each other and can be installed on a common mainboard or installed in other ways as needed. The processor can process the instructions executed in the computer device, including instructions stored in the memory or on the memory to display the graphical information of the GUI on an external input / output device (such as, a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Equally, multiple computer devices can be connected, and each device provides part of the necessary operations (for example, as a server array, a group of blade servers, or a multi-processor system). Figure 6 A processor 10 is taken as an example.

[0165] The processor 10 may be a central processing unit, a network processor, or a combination thereof. The processor 10 may further include a hardware chip. The hardware chip may be an application-specific integrated circuit, a programmable logic device, or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic, or any combination thereof.

[0166] The memory 20 stores instructions that can be executed by at least one processor 10, so as to enable at least one processor 10 to execute the method shown in the above embodiment.

[0167] The memory 20 may include a program storage area and a data storage area, wherein the program storage area may store an operating system and application programs required for at least one function; the data storage area may store data created based on the use of the computer device, etc. In addition, the memory 20 may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some optional embodiments, the memory 20 may optionally include a memory remotely located relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0168] The memory 20 may include a volatile memory, such as a random access memory; the memory may also include a non-volatile memory, such as a flash memory, a hard disk or a solid-state drive; the memory 20 may also include a combination of the above types of memory.

[0169] The computer device further includes a communication interface 30 for the computer device to communicate with other devices or a communication network.

[0170] The embodiment of the present invention also provides a computer-readable storage medium. The above-mentioned method according to the embodiment of the present invention can be implemented in hardware, firmware, or implemented as a computer code that can be recorded in a storage medium, or implemented as a computer code that is originally stored in a remote storage medium or a non-temporary machine-readable storage medium and downloaded through a network and will be stored in a local storage medium, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state drive, etc.; further, the storage medium can also include a combination of the above-mentioned types of memory. It can be understood that a computer, a processor, a microprocessor controller or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by a computer, a processor or hardware, the method shown in the above embodiment is implemented.

[0171] A portion of the present invention may be applied as a computer program product, such as a computer program instruction, which, when executed by a computer, can call or provide the method and / or technical solution according to the present invention through the operation of the computer. Those skilled in the art should understand that the form in which the computer program instruction exists in a computer-readable medium includes, but is not limited to, a source file, an executable file, an installation package file, etc. Accordingly, the way in which the computer program instruction is executed by the computer includes, but is not limited to: the computer directly executes the instruction, or the computer compiles the instruction and then executes the corresponding compiled program, or the computer reads and executes the instruction, or the computer reads and installs the instruction and then executes the corresponding installed program. Here, the computer-readable medium may be any available computer-readable storage medium or communication medium that can be accessed by the computer.

[0172] Although the embodiments of the present invention have been described with reference to the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention. Such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A hydraulic calculation method for a self-pressure irrigation system, characterized in that: Applied to the self-pressure irrigation system, the self-pressure irrigation system comprises: a water source, a first branch pipe, a second branch pipe and a main pipe with the same pipe diameter, wherein the first branch pipe and the second branch pipe are parallel, the main pipe is perpendicular to the first branch pipe and the second branch pipe respectively, a plurality of water outlets with the same diameter and height are arranged on the first branch pipe and the second branch pipe according to preset intervals, a first solenoid valve is arranged at a first intersection of the main pipe and the first branch pipe, and a second solenoid valve is arranged at a second intersection of the main pipe and the second branch pipe, water flows from the water source into the main pipe, the first branch pipe and the second branch pipe, and the method comprises: Based on a preset range of values, respectively setting the initial working pressures of the terminal water outlets of the first branch pipe and the second branch pipe; Based on the branch pipe hydraulic calculation parameters and the initial working pressure, the actual water flow rate and the actual working pressure of the terminal water outlets of the first branch pipe and the second branch pipe are calculated respectively by a first hydraulic calculation formula; Based on the branch pipe hydraulic calculation parameters, the actual water flow rate and the actual working pressure of the first water outlets adjacent to the terminal water outlets of the first branch pipe and the second branch pipe are calculated respectively by a second hydraulic calculation formula; Using the second hydraulic calculation formula, the actual water flow rate and the actual working pressure of multiple water outlets between the first water outlet of the first branch pipe and the first solenoid valve and between the first water outlet of the second branch pipe and the second solenoid valve are calculated step by step in a recursive manner; Based on the hydraulic calculation parameters of the branch pipe, the actual working pressure at the second intersection of the second branch pipe and the main pipe is calculated by a third hydraulic calculation formula; Based on the hydraulic calculation parameters of the branch pipe, a target working pressure at a second intersection of the first branch pipe and the main pipe is calculated by a fourth hydraulic calculation formula; If the absolute value of the difference between the actual working pressure and the target working pressure is greater than a first preset threshold, returning to the step of setting the initial working pressures of the terminal water outlets of the first branch pipe and the second branch pipe based on the preset range of values, respectively; If the absolute value of the difference between the actual working pressure and the target working pressure is less than or equal to the first preset threshold, the total gravitational potential energy of the main pipe is calculated by the fifth calculation formula and the sixth calculation formula based on the main pipe hydraulic calculation parameters and the branch pipe hydraulic calculation parameters; If the absolute value of the difference between the actual gravitational potential energy between the water source and the head end inlet of the main pipe and the total gravitational potential energy is less than or equal to a second preset threshold, output the actual water flow rate and the actual working pressure of the multiple water outlets of the first branch pipe and the second branch pipe one by one; If the absolute value of the difference between the actual gravitational potential energy between the water source and the head end inlet of the main pipe and the total gravitational potential energy is greater than a second preset threshold, return to the step of setting the initial working pressures of the end water outlets of the first branch pipe and the second branch pipe based on the preset range of values.

2. The method according to claim 1, characterized in that The actual water flow rate and the actual working pressure of the terminal water outlets of the first branch pipe and the second branch pipe are calculated respectively by the following first hydraulic calculation formula; Q u (a,n a )=Q s (a,n a ) Among them, Q s (a,n a ) is the outlet n at the end of branch pipe a a The actual water flow rate, μ is the outlet flow coefficient of branch a, A s The outlet n at the end of branch pipe a a The cross-sectional area of ​​water flow, H s (a,n a ) is the outlet n at the end of branch pipe a a Initial working pressure, Q u (a,n a ) is the outlet n at the end of branch pipe a a The flow rate of the upstream branch pipe section, H u (a,n a ) is the outlet n at the end of branch pipe a a The upstream section working pressure, V s (a,n a ) The end outlet n of branch pipe a a The average outlet velocity, g is the acceleration of gravity, f is the pipe friction coefficient, L s is the vertical pipe length of branch pipe a, m is the flow index, D S is the inner diameter of the vertical pipe of branch pipe a, ζ1 is the local resistance coefficient of the reducing right-angle elbow, b is the pipe diameter index, V u (a,n a ) is the outlet n at the end of branch pipe a a The average inlet velocity.

3. The method according to claim 1, characterized in that The actual water flow rate and the actual working pressure of the first water outlets adjacent to the terminal water outlets of the first branch pipe and the second branch pipe are calculated respectively by the following second hydraulic calculation formula; V u (a,n a )=Q u (a,n a ) / A z V s (a,n a-1 )=Q s (a,n a-1 ) / A s Q u (a,n a-1 )=Q s (a,n a-1 )+Q u (a,n a ) Among them, H d (a,n a-1 ) is the first outlet n of branch pipe a a-1 Downstream section working pressure, H u (a,n a ) is the outlet n at the end of branch pipe a a The upstream section working pressure, f is the pipeline friction coefficient, Q u (a,n a ) is the outlet n at the end of branch pipe a a The flow rate of the upstream branch pipe section, L z is the length of the branch pipe section between two adjacent outlets of branch pipe a, b is the pipe diameter index, D z is the inner diameter of branch pipe a, Z s (a,n a ) is the height difference between the two ends of the branch pipe section between adjacent outlets, H u (a,n a-1 ) is the first outlet n of branch pipe a a-1 The upstream section working pressure, ζ2 is the local resistance coefficient of the direct current tee of branch pipe a, V u (a,n a ) is the outlet n at the end of branch pipe a a The average inlet velocity, g is the acceleration due to gravity, A z is the cross-sectional area of ​​branch pipe a, V s (a,n a-1 ) is the first outlet n of branch pipe a a-1 The average outlet velocity, A s The outlet n at the end of branch pipe a a The cross-sectional area of ​​water flow, Q s (a,n a-1 ) is the first outlet n of branch pipe a a-1 The actual water flow rate, μ is the outlet flow coefficient of the branch pipe, H s (a,n a-1 ) is the first outlet n of branch pipe a a-1 The actual working pressure, D S L is the inner diameter of the vertical pipe of branch pipe a, s is the vertical pipe length of branch a, ζ3 is the local resistance coefficient of the baffle tee of branch a, Q u (a,n a-1 ) is the first outlet n of branch pipe a a-1 The flow rate of the upstream branch pipe section.

4. The method according to claim 1, characterized in that: Calculate the actual water flow rate and the actual working pressure at the second intersection of the second branch pipe and the main pipe by the following third hydraulic calculation formula; Q z (c)=Q u (c,1) Among them, H u (c,1) is the working pressure of the upstream section of the outlet of the first end of the second branch pipe, f is the friction coefficient of the pipe, Q u (c,1) is the flow rate of the upstream section of the outlet of the second branch pipe, m is the flow index, L c D is the horizontal distance from the outlet of the second branch pipe to the main pipe. z is the inner diameter of the branch pipe, Z c0 is the height difference from the outlet of the first end of the second branch pipe to the main pipe, ζ4 is the local resistance coefficient of the valve at the first end of the branch pipe, V u (c,1) is the average inlet velocity of the outlet at the first end of the second branch pipe, g is the acceleration due to gravity, Q z (c) is the total water flow rate at the second solenoid valve, H u (g) is the actual working pressure at the second intersection of the second branch pipe and the main pipe, H z (c) is the total working pressure at the second solenoid valve, ζ6 is the local resistance coefficient of the baffle three-way valve at the second branch pipe, V z (c) is the average flow rate at the second solenoid valve.

5. The method according to claim 1, characterized in that Calculate the target water flow rate and target working pressure at the second intersection of the first branch pipe and the main pipe by the following fourth hydraulic calculation formula; Q z (a)=Q u (a,1) Q g (a)=Q z (a) again Substituting in, we get: Among them, H u (a,1) is the working pressure of the upstream section of the outlet of the first branch pipe, f is the friction coefficient of the pipe, Q u (a,1) is the flow rate of the upstream section of the outlet of the first branch pipe, m is the flow index, L a D is the horizontal distance from the outlet of the first branch pipe to the main pipe. z is the inner diameter of the branch pipe, Z a0 is the height difference from the outlet of the first branch pipe to the main pipe, ζ4 is the local resistance coefficient of the valve at the first end of the branch pipe, V u (a,1) is the average inlet velocity of the first outlet of the first branch pipe, g is the acceleration due to gravity, Q z (a) is the total water flow rate at the first solenoid valve, H d (g) is the intermediate parameter, H z (a) is the total working pressure at the first solenoid valve, Q g (a) is the total outflow rate at the first branch, L g is the distance between the first intersection point and the second intersection point, D g is the inner diameter of the main pipe, Z0 is the height difference between the first intersection and the second intersection, ζ5 is the sum of the local resistance coefficients of the DC tees on the main pipe between the first intersection and the second intersection, V z (a) is the average flow velocity at the first solenoid valve, V z (c) is the average flow velocity at the second solenoid valve, ζ7 is the local resistance coefficient of the DC tee at the second branch pipe, H u '(g) is the target working pressure at the second intersection of the first branch pipe and the main pipe.

6. The method according to claim 1, characterized in that The total gravitational potential energy of the main pipe is calculated by the fifth and sixth calculation formulas as follows; When there is an intersection point between the second branch pipe and the water inlet of the main pipe, the total gravitational potential energy of the main pipe is calculated by the following fifth calculation formula; Q g =Q z (a)+Q z (c) When there is no intersection between the second branch pipe and the water inlet of the main pipe, the total gravitational potential energy of the main pipe is calculated by the following sixth calculation formula; Q g =Q z (a)+Q z (c) Among them, Q g is the total outflow flow of the main pipe, Q z (a) is the total water flow rate at the first solenoid valve, Q z (c) is the total water flow rate at the second solenoid valve, Z g ′ is the total gravitational potential energy of the main pipe, H u (g) is the actual working pressure at the second intersection of the second branch pipe and the main pipe, f is the pipeline friction coefficient, m is the flow index, L gs D is the length of the pipe section between the water source and the main pipe inlet, gs is the inner diameter of the pipe between the water source and the main pipe inlet, b is the pipe diameter index, ζ8 is the local resistance coefficient of the main pipe head valve, V g is the average flow velocity of the main pipe, g is the acceleration of gravity, L0 is the length of the pipe section between the second branch pipe and the water inlet of the main pipe, Z1 is the height difference between the second branch pipe and the water inlet of the main pipe, and ζ9 is the sum of the local resistance coefficients of each DC three-way valve at the water inlet of the main pipe.

7. A hydraulic calculation device for a self-pressure irrigation system, characterized in that: Applied to the self-pressure irrigation system, the self-pressure irrigation system comprises: a water source, a first branch pipe, a second branch pipe and a main pipe with the same pipe diameter, wherein the first branch pipe and the second branch pipe are parallel, the main pipe is respectively perpendicular to the first branch pipe and the second branch pipe, a plurality of water outlets with the same diameter and height are arranged on the first branch pipe and the second branch pipe according to preset intervals, a first solenoid valve is arranged at a first intersection of the main pipe and the first branch pipe, and a second solenoid valve is arranged at a second intersection of the main pipe and the second branch pipe, water flows from the water source into the main pipe, the first branch pipe and the second branch pipe, and the device comprises: A parameter setting module, used to set the initial working pressures of the terminal water outlets of the first branch pipe and the second branch pipe respectively based on a preset range of values; A first calculation module, used to calculate the actual water flow rate and the actual working pressure of the terminal water outlets of the first branch pipe and the second branch pipe respectively based on the branch pipe hydraulic calculation parameters and the initial working pressure through a first hydraulic calculation formula; A second calculation module, used to calculate the actual water flow rate and the actual working pressure of the first water outlets adjacent to the terminal water outlets of the first branch pipe and the second branch pipe respectively based on the branch pipe hydraulic calculation parameters and by a second hydraulic calculation formula; a third calculation module, for recursively calculating the actual water flow rate and the actual working pressure of multiple water outlets between the first water outlet of the first branch pipe and the first solenoid valve and between the first water outlet of the second branch pipe and the second solenoid valve; a fourth calculation module, configured to calculate the actual working pressure at the second intersection of the second branch pipe and the main pipe based on the branch pipe hydraulic calculation parameter and by using a third hydraulic calculation formula; a fifth calculation module, configured to calculate a target working pressure at a second intersection of the first branch pipe and the main pipe based on the branch pipe hydraulic calculation parameter and using a fourth hydraulic calculation formula; A first optimization module, configured to return the module for setting the initial working pressures of the terminal water outlets of the first branch pipe and the second branch pipe respectively based on a preset range of values ​​if the absolute value of the difference between the actual working pressure and the target working pressure is greater than a first preset threshold; a sixth calculation module, configured to calculate the total gravitational potential energy of the main pipe by using the fifth calculation formula and the sixth calculation formula based on the main pipe hydraulic calculation parameters and the branch pipe hydraulic calculation parameters if the absolute value of the difference between the actual working pressure and the target working pressure is less than or equal to the first preset threshold; a parameter output module, configured to output the actual water flow rates and actual working pressures of the plurality of water outlets of the first branch pipe and the second branch pipe one by one if the absolute value of the difference between the actual gravitational potential energy between the water source and the head end inlet of the main pipe and the total gravitational potential energy is less than or equal to a second preset threshold; The second optimization module is used to return to the module for setting the initial working pressures of the end water outlets of the first branch pipe and the second branch pipe respectively based on the preset range value if the absolute value of the difference between the actual gravitational potential energy between the water source and the head end inlet of the main pipe and the total gravitational potential energy is greater than a second preset threshold.

8. A computer device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the hydraulic calculation method of the self-pressure irrigation system according to any one of claims 1 to 6 by executing the computer instructions.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the hydraulic calculation method for the self-pressure irrigation system according to any one of claims 1 to 6.

10. A computer program product, characterized in that The method comprises computer instructions for causing a computer to execute the hydraulic calculation method for the self-pressure irrigation system according to any one of claims 1 to 6.

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