CN114357913A - Open channel junction hydrodynamic simulation method based on momentum conservation and Riemann solution - Google Patents

Open channel junction hydrodynamic simulation method based on momentum conservation and Riemann solution Download PDF

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CN114357913A
CN114357913A CN202210038436.4A CN202210038436A CN114357913A CN 114357913 A CN114357913 A CN 114357913A CN 202210038436 A CN202210038436 A CN 202210038436A CN 114357913 A CN114357913 A CN 114357913A
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孙万光
马军
栾宇东
苑润保
樊祥船
范宝山
姜彪
谢成海
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China Water Northeastern Investigation Design & Research Co ltd
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Abstract

The invention relates to the technical field of computational fluid dynamics, in particular to a hydrodynamic force simulation method of an open channel junction based on momentum conservation and Riemann solution; the invention provides an open channel intersection hydrodynamic force simulation method based on momentum conservation and Riemann solution, which adopts a method for separately solving branch of a river points and a branch channel, takes a momentum conservation equation as a branch of a river point conservation equation in the aspect of branch of a river point connection equation, increases a side pressure term generated due to the width change of an overflow section, constructs a branch of a river point supplementary equation based on the Riemann problem solution, does not need an empirical coefficient, and has higher precision and stronger adaptability.

Description

Open channel junction hydrodynamic simulation method based on momentum conservation and Riemann solution
Technical Field
The invention relates to the technical field of computational fluid dynamics, in particular to a hydrodynamic force simulation method for an open channel junction based on momentum conservation and Riemann solution.
Background
Natural rivers, irrigation and drainage channels and urban sewage pipe networks are all connected through branch of a river points, hydrodynamic simulation of the system is usually solved as a one-dimensional problem, but the water flow motion state at the intersection is very complex (including flow separation, secondary flow and the like), the required parameters are more in calculation, and the high-precision numerical simulation of the one-dimensional hydrodynamic force becomes the focus of industrial attention. Compared with a single river reach, the river network hydrodynamic calculation process needs to supplement branch of a river point connection conditions, also called inner boundary conditions. According to the different processing modes of boundary at point branch of a river, the method can be divided into: branch of a river point and branch channel coupling solution; branch of a river points and branch channels are solved separately.
Branch of a river points and branched channel coupling solving method is represented by an implicit differential format, all branched channels are influenced mutually, all branched channels must be simulated at the same time, and in order to improve the calculation efficiency, an overall solution, a hierarchical solution and an iteration method are developed successively. For a large river network, the discrete equation is a large matrix with almost full rank, and the solving efficiency is low.
The independent solution method of branch of a river points and the branched channel is to establish a branch of a river point connection closed equation set comprising a conservation equation and a complementary equation, and further solve branch of a river point variables to serve as boundary conditions of branched channel calculation. According to the method, branch of a river points and branch channels are decoupled, the calculation accuracy and efficiency are high, and conditions are created for parallel calculation.
The conservation equations include mass conservation equations, energy conservation, or momentum conservation equations at point branch of a river. The supplementary equation is branch of a river point and branch channel connection equation, and characteristic line equation is mostly adopted in the past research.
In addition to the conservation of mass equation, five classical methods of constructing branch of a river point conservation equations: akan provides an energy conservation method at point branch of a river, namely, the water levels of all branch channels at point branch of a river are equal, and the flow velocity water head is ignored; firstly, the Taylor adopts a momentum conservation equation to research the problem of high water level congestion of a confluence port; providing an branch of a river inching momentum conservation method by Gurram, and introducing an included angle parameter between the flow direction of a branch water flow and a main flow; hsu expands the method of Gurram, introduces energy and momentum correction coefficient; shabayek proposes a conservation equation of momentum at branch of a river points, and cancels the limit that the branch channel water depth and the river width at branch of a river points are equal. When the froude number is larger than 0.35, the calculation accuracy of the method based on the conservation of energy is poor. The method based on the momentum conservation equation ignores the lateral pressure generated by the width change of the flow cross section in the derivation process, only adjusts the lateral pressure through the momentum or energy correction coefficient, and needs to calibrate according to the geometric shape of the point branch of a river and the hydrodynamic force characteristics in the use process, so that the universality is poor.
In the aspect of supplementary equations, as an alternative to the characteristic line equation, goudiany studies the Riemann problem at the point branch of a river of the river network to prove the uniqueness of the knowledge; briani proposes an branch of a river point connection equation based on the Riemann problem solution; elshobakaki carries out theoretical analysis on the Riemann problem at branch of a river points under the conditions of asymmetric branched channel and discontinuous channel bottom, and provides a branch of a river-point supplement equation based on the Riemann problem solution.
Disclosure of Invention
Technical problem to be solved
The invention aims to overcome the defects of the method in the background art and provides a hydrodynamic simulation method of an open channel junction based on momentum conservation and Riemann solution.
(II) technical scheme
The open channel junction hydrodynamic force simulation method based on momentum conservation and Riemann solution comprises the following steps:
s1, describing the water flow motion of the open channel by adopting a conservation type Saint Vietnam equation set, and constructing an open channel hydrodynamic force control equation;
s2, discretizing a control equation by adopting a Godunov format finite volume method;
s3, constructing branch of a river point connection equations which comprise a mass conservation equation, a momentum conservation equation and a supplementary equation;
and S4, solving the branch of a river point connection equation.
The method comprises the following specific steps:
(1) open channel water power control equation
The conservation type Saint Vietnam equation set is adopted to describe the flow motion of the open channel, and the vector expression of the conservation type Saint Vietnam equation set is as follows:
Figure BDA0003469068070000031
Figure BDA0003469068070000032
in the formula: u is a variable; f is flux; s is a source item; t is time; x is a spatial coordinate; a (x, t) is the flow cross-section area; q is the flow; g is the acceleration of gravity; s0Is the bed surface slope; sfIs the friction drag ratio drop; i is1And I2Static moment and side pressure, respectively, the expression is as follows:
Figure BDA0003469068070000033
in the formula: h is the depth of water, and b (x, η) is the width of the section.
Bed surface gradient S in natural river0The variation is large, and the bottom slope source item is usually avoided in the source item processing. Cunge gives the pair I1The expression of the derivation:
Figure BDA0003469068070000041
thus, the source term in equation (2) can be rewritten as:
Figure BDA0003469068070000042
in the formula:
Figure BDA0003469068070000043
when the water level Z is regarded as a constant I1The partial derivatives for x.
The source term is processed by using a side pressure term I2Height of bed surface0Converted into a static moment I1The partial derivatives are high in precision and convenient to calculate.
(2) Open channel hydrodynamic force control equation numerical dispersion
Discretizing a control equation by using a finite volume method in a Godunov format, wherein the expression is as follows:
Figure BDA0003469068070000044
in the formula: i is the serial number of the calculation unit; n is the time; delta xiCalculating the length of the unit i; Δ t is the step of the calculation time,
Figure BDA0003469068070000045
the maximum wave speed at the moment n; fi+1/2And Fi-1/2The fluxes at the i +1/2 and i-1/2 interfaces, respectively.
Calculating the flux at the interface by adopting an HLLC approximate Riemann solver, wherein the flux expression is as follows:
Figure BDA0003469068070000046
in the formula: u shapeLAnd URVariables on the left and right sides of the interface respectively; fLAnd FRLeft and right interfacial flux, respectively; u shape*LAnd U*RRespectively a left variable and a right variable of the intermediate wave, which are variables to be solved; f*LAnd F*RThe flux on the left side and the right side of the middle wave respectively; sLAnd SRThe left and right wave velocities of the interface, respectively.
The wave velocity is estimated by the following method:
SL=uL-qLaL,SR=uR+qRaR (8)
in the formula: u. ofLAnd uRFlow rates on the left and right sides of the interface, respectively; a isLAnd aRThe wave velocities of the gravity waves on the left side and the right side of the interface are respectively; q. q.sKThe expression of (K ═ L, R) is as follows:
Figure BDA0003469068070000051
in the formula:
Figure BDA0003469068070000052
for the estimate of the mid-wave accurate water depth h, it can be estimated using the following equation:
Figure BDA0003469068070000053
in the formula: a isTRIs an estimated value of the wave velocity a of the gravity wave based on the assumption that both the left side and the right side of the interface are sparse waves.
Q*、A*And S*The expression of (a) is as follows:
Figure BDA0003469068070000054
in the formula, subscript R represents the right side, and subscript L represents the left side.
(3) Branch of a river Point connection equation
The branch of a river point connection equation includes: mass conservation equations, momentum conservation equations, and replenishment equations.
1) Conservation of mass equation
The mass conservation equation, i.e., the inflow and outflow at point branch of a river, is equal, and the expression is as follows:
Figure BDA0003469068070000055
in the formula: n is the total number of branch channels connected at branch of a river points, and k is a serial number; qk*And Ak*Respectively the k branched channel flow and the flow cross section area at branch of a river points; x is the number ofkDetermining k branch channel space coordinates; l iskIs the k branch channel end spatial coordinate.
2) Equation of conservation of momentum
The assumption of equal water levels upstream of the junction in the conservation of momentum equation (junction case, see FIG. 1) was confirmed in multiple sets of basin tests. In the momentum conservation expression, the side pressure term generated due to the change in the section width is increased. In general, the component of the side pressure term in the x-axis direction is negligible under conditions of small section width variation. If the change in the cross-sectional width is large, the lateral pressure term must be taken into account, which is a main cause of the water level choking upstream of the confluence port.
The specific expression of the conservation of momentum equation at point branch of a river is as follows:
Figure BDA0003469068070000061
in the formula: z is water level; SF ═ Q2/gA+I1;FfIs frictional resistance; wxIs the component of the water body gravity along the x-axis; theta is the included angle of the branch channel; i is1,latThe side static moment is generated due to the change of the section width;
Figure BDA0003469068070000062
the angle between the side edge and the x-axis (see figure 2),
Figure BDA0003469068070000063
b is the width of the cross section.
I1,latTo add new terms, it can be seen from the shaded portion in fig. 1 that a flow separation zone is generated after branch channel confluence, and the width b of the flow cross section is adjusted from b within the flow cross section width adjustment distance L1+b2cos θ to b3Thereby generating a sidewall pressure. Adjusting distance L ═ b2/sinθ+Ls,LsFor separation zone length: under the condition of slow flow,
Figure BDA0003469068070000064
Fdto the Froude number downstream of the junction, RQ=Q2/Q3
The side static moment expression is as follows:
Figure BDA0003469068070000065
in the formula: s and S0Respectively a water surface drop and a canal bottom drop; ziAnd Zb,iI water level and channel bottom elevation.
3) Supplementary equation
In the complementary equation, a Riemann problem is constructed according to branch of a river points and the initial values of the branched channel sections (see fig. 3), an algebraic expression based on the solution of the Riemann problem is constructed, and the connection relationship between the branched channel and branch of a river points is established as the complementary equation, wherein the expression is as follows:
Figure BDA0003469068070000071
in the formula: qkAnd AkThe initial flow and the flow cross-sectional area at the point branch of a river of the k branched channel connection respectively;
Figure BDA0003469068070000072
(4) branch of a river point join equation solution
Taking the junction of the attached drawing 1 as an example, the branch of a river point connection equation has 6 unknowns, and the solution is carried out by adopting a step-by-step and single-variable solution method.
The method comprises the following specific steps:
1) first assume Z3*With Z2*Or Z1*As variables, make it satisfy the conservation of momentum condition:
(ii) known of Z3*Calculating the corresponding flow cross-sectional area A3*Solving for Q according to equation (15)3*
② setting Z1*Value and make Z2*=Z1*Calculating the corresponding flow cross-sectional area A1*、A2*According to the formula (15)Q solution1*、Q2*
Thirdly, carrying out univariate (Z) on the formula (13) by adopting a third-order convergence iteration method1*) Solving, the expression is as follows:
Figure BDA0003469068070000081
iteration stops when the following conditions are met:
Figure BDA0003469068070000082
in the formula: x*Is a variable; epsilon1Is a set error tolerance value.
2) With Z3*And (3) repeating the step 1) for variable, and carrying out iterative solution on the formula (12) by adopting a three-order convergence iterative method until convergence is achieved, so that the condition of mass conservation is met.
(III) advantageous effects
The invention provides an open channel intersection hydrodynamic force simulation method based on momentum conservation and Riemann solution, which adopts a method for separately solving branch of a river points and a branch channel, takes a momentum conservation equation as a branch of a river point conservation equation in the aspect of branch of a river point connection equation, increases a side pressure term generated due to the width change of an overflow section, constructs a branch of a river point supplementary equation based on the Riemann problem solution, does not need an empirical coefficient, and has higher precision and stronger adaptability.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only for the present invention and protect some embodiments, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.
FIG. 1 is a schematic view of a bus port;
FIG. 2 is a schematic illustration of the Riemann problem solution at point branch of a river;
FIG. 3 is a side pressure diagram generated by a change in section width;
FIG. 4 is a schematic view of a sink test;
FIG. 5 is a schematic cross-sectional view of a river channel with a diversion port;
FIG. 6 is a split port two-dimensional computational meshing;
FIG. 7 is a river cross-section geometry;
FIG. 8 is a comparison of results of one and two-dimensional flow calculations.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In the description of the present invention, it should be noted that, as the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. appear, their indicated orientations or positional relationships are based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Moreover, the terms "first," "second," and "third," if any, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" should be interpreted broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
(1) Summary of the invention
A set of water tank tests (shown in figure 4) are designed by Pinto Coelho, the width of each water tank is 0.3m, the depth of each water tank is 0.5m, the length of each main tank is 10m, the bottom slope of each water tank is 0.14 percent, and the included angles theta of the branched channels are respectively 30 degrees and 60 degrees. The range of froude number changes for each branch channel under different experimental protocols are shown in table 1.
TABLE 1 variation of branch of a river Froude numbers
Figure BDA0003469068070000101
In the past, in an branch of a river-point momentum conservation equation, a branch is introduced to lead the included angle between the flow direction of water flow at a gathering part and a main groove, or momentum or kinetic energy correction coefficients are introduced, and the parameters are determined through experiments and are limited in application, so that the invention does not carry out comparative analysis. The Taylor formula does not introduce parameters which need to be determined by experiments, and the application is simpler. The results of the calculation of the method of the invention are compared with the test values and with the results of the calculation of the Taylor method, which are shown in tables 2 and 3, and the expression of the Taylor method is as follows:
Figure BDA0003469068070000102
in the formula: ry=y2/y8Y is the water depth, 2 and 8 are the measuring points; rQ=Q4/Q8Q is the flow, 4 and 8 are the measuring points; f8Froude number at point 8; theta is the included angle between the branch and the main groove.
The error is calculated using the following equation:
Figure BDA0003469068070000103
in the formula:
Figure BDA0003469068070000104
is a test value;
Figure BDA0003469068070000105
is a calculated value.
Table 2 comparison of the calculation results with the actual measurement values when θ is 30 °
Figure BDA0003469068070000106
Figure BDA0003469068070000111
Table 3 comparison of the measured values with the calculation results when θ is 60 °
Figure BDA0003469068070000112
As can be seen from the comparison results in the table, when θ is 30 °, the Taylor formula calculates the relative error as 3.37% on average and the standard deviation as 3.06% compared with the measured value; the average calculated relative error of the method is 1.9 percent, and the standard deviation is 0.84 percent. When theta is 60 degrees, compared with an actually measured value, the calculated relative error of the Taylor formula is averagely 3.25 percent, and the standard deviation is 2.48 percent; the average calculated relative error of the method is 1.06 percent, and the standard deviation is 1.26 percent; the mean value and the standard deviation of the relative errors of the method are obviously lower than the calculation result of the Taylor formula.
The flow state at the junction of the open channel is very complex, the head loss is large, the energy conservation method at the point branch of a river has overlarge deviation with the actual method, and the momentum conservation method can accurately express the water flow motion state. The conventional branch of a river-point momentum conservation equation ignores the lateral pressure term generated by the change of the section width, and in the test, the relative error calculated by the Taylor formula can reach 9.03 percent at most. Under the condition of slow flow, the branch inlet manifold sharply narrows the area of the flow cross section, so that a relatively obvious lateral pressure can be generated, which is a main reason of high water level upstream of the confluence port. In the calculation process of the formula, parameters which need to be determined through tests do not need to be introduced, and the application range is wide.
(2) Example of flow dividing port
The open channel tap is common in the estuary delta area, and the accurate calculation of the splitting ratio of each branch output flow after the water flow passes through branch of a river points is a key problem in the calculation of one-dimensional river network hydrodynamic force.
The embodiment is designed into a simple branched river channel (see the attached figure 5), and the branched channel splitting ratio under the non-constant flow condition is calculated. In the two-dimensional hydrodynamic calculation process, branched channels and branch of a river points are not distinguished any more, grid division and calculation are carried out uniformly, and Ghostine verifies the accuracy of a simulation result of a two-dimensional numerical method at the branch of a river point of an open channel through experiments. Therefore, the one-dimensional result is verified by adopting a two-dimensional hydrodynamic calculation result (Delft-3 d software is adopted, the size of a grid is about 10m, and calculation grid division is shown in an attached figure 6), and the applicability of the algorithm in a natural river network is tested. The length of each of the 3 branch channels is 1.5km, the included angles of the branch channels 2, 3 and 1 are 45 degrees, the section geometric shapes of the branch channels 1 and 3 are close to each other, the river width of the branch channel 2 is smaller than that of the branch channel 3, and the section view is shown in the attached drawing 7.
The branch is 1 entry for flow boundary condition, and branch 2 and branch 3 export are water level flow relation boundary condition, and the river course roughness is 0.035. The results of the first and second dimensional calculations are compared and shown in FIG. 8.
As can be seen from the figure, the results of the two-dimensional calculation of the first time-dependent change process and the second time-dependent change process of the cross-sectional flow of R2-1# and R3-1# are well matched; the one-dimensional calculation result of the total-period splitting ratio of the branch channel 3 at the confluence opening is 52.26%, and the two-dimensional calculation result is 52.55%; at the moment of peak flow, the one-dimensional calculation result of the R3-1# section flow is 1801m3(s) two-dimensional calculation result is 1818m3And/s, the relative error of the two is less than 1 percent. Therefore, the one-dimensional river network calculation result is closer to the two-dimensional hydrodynamic calculation result.
In the branch of a river point connection equation, a momentum conservation equation is introduced, which is the root cause that the results of one-dimensional and two-dimensional calculations are well matched. For the complex water flow motion state at the point branch of a river, the applicability of the momentum conservation equation is obviously superior to that of the energy conservation equation, and the momentum conservation equation in the invention abandons empirical coefficients, so that the application range of the method is further expanded. In addition, an branch of a river point supplement equation based on a Riemann problem solution is constructed, and the flux between the branched channel and the branch of a river point can be accurately calculated under the condition of sparse waves or shock waves.
In conclusion, the hydrodynamic force mathematical model of the branch channel and the open channel intersection completely decoupled at point branch of a river is established in the invention: in the aspect of branch of a river point connection equation, a new branch of a river point momentum conservation equation is provided, any empirical coefficient is not needed, the side pressure generated by the change of the section width is increased, and a branch of a river point supplement equation based on a Riemann problem solution is constructed; in the aspect of open channel water power, a conservation type Saint-Vietnam equation is used as a control equation, and based on a Godunov format, an HLLC approximate Riemann solver is used for calculating the interface flux. The verification proves that the calculation result of the invention is well matched with the test data or the two-dimensional calculation result. The research result provides a new method for high-precision numerical simulation of hydrodynamic force at the intersection of the one-dimensional open channel.
In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, aspects, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The preferred embodiments of the invention disclosed above are intended to be illustrative only. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims (4)

1. The open channel junction hydrodynamic force simulation method based on momentum conservation and Riemann solution is characterized by comprising the following steps of:
s1, describing the water flow motion of the open channel by adopting a conservation type Saint Vietnam equation set, and constructing an open channel hydrodynamic force control equation;
s2, discretizing a control equation by adopting a Godunov format finite volume method;
s3, constructing branch of a river point connection equations which comprise a mass conservation equation, a momentum conservation equation and a supplementary equation;
and S4, solving the branch of a river point connection equation.
2. The method for hydrodynamic simulation of an open channel junction based on conservation of momentum and Riemann' S solution according to claim 1, wherein in S3, the specific expression of the conservation of momentum equation at point branch of a river is as follows:
Z1=Z2
Figure FDA0003469068060000011
in the formula: z is water level; SF ═ Q2/gA+I1;FfIs frictional resistance; wxIs the component of the water body gravity along the x-axis; theta is the included angle of the branch channel; i is1,latThe side static moment is generated due to the change of the section width;
Figure FDA0003469068060000012
is the included angle between the side edge and the x-axis,
Figure FDA0003469068060000013
b is the width of the cross section, and L is the adjustment distance of the width of the cross section;
within the flow section width adjusting distance L, the flow section width b is adjusted from b1+b2cos θ to b3Thereby creating a sidewall pressure;
L=b2/sinθ+Ls,Lsfor separation zone length: under the condition of slow flow,
Figure FDA0003469068060000014
Fdto the Froude number downstream of the junction, RQ=Q2/Q3
The side static moment expression is as follows:
Figure FDA0003469068060000021
in the formula: s and S0Respectively a water surface drop and a canal bottom drop; ziAnd Zb,iI water level and channel bottom elevation.
3. The method for hydrodynamic simulation of the intersection of the open channel based on momentum conservation and the Riemann solution as claimed in claim 2, wherein the Riemann problem is constructed according to branch of a river points and initial values of the section of the branched channel, an algebraic expression based on the Riemann problem solution is constructed, and a connection relationship is established between the branched channel and branch of a river points, wherein the expression is as follows:
Figure FDA0003469068060000022
in the formula: qkAnd AkThe initial flow and the flow cross-sectional area at the point branch of a river of the k branched channel connection respectively;
Figure FDA0003469068060000023
4. the method for simulating the hydrodynamic force at the intersection of the open channel based on the conservation of momentum and the Riemann solution as claimed in claim 1, wherein in S4, a step-by-step and univariate solution method is adopted for solving;
the method comprises the following steps:
1) first assume Z3*With Z2*Or Z1*As variables, make it satisfy the conservation of momentum condition:
(ii) known of Z3*Calculating the corresponding flow cross-sectional area A3*Solving for Q according to equation (15)3*
② setting Z1*Value and make Z2*=Z1*Calculating the corresponding flow cross-sectional area A1*、A2*Solving for Q according to equation (15)1*、Q2*
Thirdly, carrying out univariate (Z) on the formula (13) by adopting a third-order convergence iteration method1*) Solving, the expression is as follows:
Figure FDA0003469068060000031
iteration stops when the following conditions are met:
Figure FDA0003469068060000032
in the formula: x*Is a variable; epsilon1Is a set error tolerance value;
2) with Z3*And (3) repeating the step 1) for variable, and iteratively solving the mass conservation equation by adopting a three-order convergence iteration method until convergence is achieved, so that the mass conservation condition is met.
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CN116415526A (en) * 2023-04-07 2023-07-11 中国水利水电科学研究院 Irrigation area canal network water delivery and distribution optimization regulation method based on hydrodynamic simulation
CN116415526B (en) * 2023-04-07 2024-05-07 中国水利水电科学研究院 Irrigation area canal network water delivery and distribution optimization regulation method based on hydrodynamic simulation
CN116757003A (en) * 2023-08-18 2023-09-15 长江三峡集团实业发展(北京)有限公司 Plain river network simulation method, plain river network simulation device, computer equipment and medium
CN116757003B (en) * 2023-08-18 2024-01-05 长江三峡集团实业发展(北京)有限公司 Plain river network simulation method, plain river network simulation device, computer equipment and medium
CN117669408A (en) * 2023-11-13 2024-03-08 广东省水利水电科学研究院 River network safety assessment method and system based on hydrodynamic force simulation

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