KR101497993B1  Method and apparatus for analyzing river sedimentation and flushing using quasi2dimensional quasisteady model  Google Patents
Method and apparatus for analyzing river sedimentation and flushing using quasi2dimensional quasisteady model Download PDFInfo
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 KR101497993B1 KR101497993B1 KR20140114507A KR20140114507A KR101497993B1 KR 101497993 B1 KR101497993 B1 KR 101497993B1 KR 20140114507 A KR20140114507 A KR 20140114507A KR 20140114507 A KR20140114507 A KR 20140114507A KR 101497993 B1 KR101497993 B1 KR 101497993B1
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Abstract
Description
The present invention relates to a river sedimentation analysis technique, and more particularly, to a river sedimentation analysis technique using a quasirectification model.
If it was important to build a dam to secure water resources in the 20th century, maintaining the function of dams for the same purpose, the low capacity, will be the topic of discussion in the 21st century. This is because some of the dams have already been developed and there are not many countries that can build additional dams due to various environmental problems.
Morris et al. (2007) report that dams around the world are reducing capacity by 1% per year due to reservoir retirement. According to Ryu Tae Sang et al. (2010) in Korea, 9 dams over 20 years after the freshwater eruption have reached 346 million ㎥ in the last 10 years, which is 6 to 7 times of the reservoirs of Hwabang Dam and Hwabuk Dam. In addition, it is reported that Daecheong Dam increased by 5.4 times from 114m3 / ㎢ / yr in 1991 to 616m3 / ㎢ / yr in 2006. These data suggest that Korea's dams are no longer free from reservoir retirement problems.
Generally, the water depth is increased by the drainage effect in the downstream direction from the lower stream where the dam is located downstream, and the flow rate is decreased accordingly. At this time, the shear stress of the bed is proportional to the square of the flow velocity. Further, the hydrostatic pressure increases toward the downstream, making it difficult to move the bed soil. Therefore, the similarity moved upstream is deposited near the dam, which is a key mechanism of the reservoir retirement phenomenon.
The history of numerical analysis on river bed fluctuations in rivers is not short. The first studies have segregated the flow and bed soil conservation equations based on the fact that the velocities of the bed and the bed are very different. Thereafter, a model for direct analysis of the unsteady flow equations was also presented to simulate the fluctuation of the bed due to rapid or transient flow. However, since these models do not have a steady flow assumption for the flow, the computational complexity is so large that it is difficult to apply to longterm deformation prediction problems.
SUMMARY OF THE INVENTION The present invention is directed to a method and apparatus for analyzing and dropping streams using quasitwodimensional quasirectification models.
A problem to be solved by the present invention is to provide a method and an apparatus for analyzing a stream leaving and breaking by applying a quasitwodimensional quasirectifying model capable of providing an accuracy that does not fall far below that of an unsteady flow equation model with much less computational complexity than an unsteady flow equation There is.
SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and an apparatus for analyzing river discharge and distribution using a quasitwodimensional quasirectification model capable of providing a longterm prediction result.
The problem to be solved by the present invention is to provide a method and apparatus for providing a lateral distribution of depthaveraged velocity, bed shear stress, lateral shear and channel geometry, A quasitwodimensional quasirectifying model is applied to a method of and apparatus for analyzing a stream leaving and discharging.
The solution to the problem of the present invention is not limited to those mentioned above, and other solutions not mentioned can be clearly understood by those skilled in the art from the following description.
The quasitwodimensional quasirectification model according to one aspect of the present invention is applied to a river sedimentation and distribution analysis method using a quasitwodimensional quasirectification model using a computer.
The computer comprising:
(a) Based on a onedimensional quasirectification model for given bedside data including initial stream topography, flow, sediment particle size, sediment flow, tributaries, etc., Calculating a depth of water;
(b) calculating a total amount of similarity per unit width of the longitudinal section by using the calculated water depth average velocity and the depth of the section;
(c) calculating the longitudinal undersurface height in accordance with the onedimensional quasirectification model using the calculated total amount per longitudinal unit width;
(d) calculating the lateral flow velocity distribution according to the lateral distribution method using the average flow velocity, water depth, and bottom height of the vertical longitudinal section;
(e) calculating a lateral similarity distribution based on the lateral flow velocity distribution; And
(f) calculating the lateral river bed variation based on the lateral similarity distribution.
According to an embodiment, (b) calculating a total similarity amount per unit width of the longitudinal cross section may be calculated by the following equation
And calculating a solution of the solution,
Where q _{s} is the total amount of sediment per unit width to be calculated, R is the submerged specific gravity, d _{50} is the median size of the sediment particles,
Is the dimensionless shear stress, C _{f} is the bed resistance coefficient, and g is the gravitational acceleration.According to an embodiment, (b) calculating a total similarity amount per unit width of the longitudinal cross section may be calculated by the following equation
And calculating a solution of the solution,
Where C _{s} is the fluxbased mass concentration, a _{1} and a _{2} are the empirical parameters,
Is the specific weight of sediment in sedimentladen flow, Is the specific weight of sediment, May be the descent rate of the sediment.According to one embodiment, (c) the step of calculating the longitudinal undersurface comprises:
The following equation
And calculating a solution of the solution,
here,
Is bed elevation, t is time, Is the porosity of the bed material, Is the sediment load per unit width, and x may be the longitudinal distance from the upstream to the corresponding point.According to one embodiment, (d) calculating the lateral flow velocity distribution according to the lateral distribution method comprises
The following equation
And calculating a solution of the solution,
Where x is the longitudinal distance, y is the lateral distance,
G is the gravitational acceleration, H is the depth of water, S _{x} is the bed slope in the x direction, Is the bed shear stress, B _{g} is the shear stress S _{y} is the ydirection slope of the bed, Is the depthaveraged lateral shear stress, May be term due to secondary currents.According to one embodiment, the depthaveraged transverse shear stress
Is expressed by the following equation
Lt; / RTI >
here
Is the eddy viscosity, which determines the shear stress between water columns due to the difference in flow velocity, Is the density of water and U _{d} is the depthaveraged velocity in the x direction.According to one embodiment, the secondary flow term
Is expressed by the following equation
Lt; / RTI >
here,
And Are the timeaveraged xdirection and ydirection components of the flow velocity, z is the vertical distance and H is the water depth, Can be the density of water.According to one embodiment, the method of analyzing stream leaving and distributing using the quasitwodimensional quasirectifier model may further include repeating steps (a) to (f) for each time unit for longterm simulation have.
According to one embodiment, the method of analyzing a stream leaving and breaking by applying the quasitwodimensional quasirectification model further comprises: (g) calculating a deformation of a bed slope using an activity algorithm after the step (f) can do.
A computer program according to another aspect of the present invention may be stored in a recording medium for executing each step of a stream leaving and breaking analysis method in which a quasitwodimensional quasirectifying model according to embodiments of the present invention is applied to a computer.
According to another aspect of the present invention, there is provided an apparatus for analyzing a stream withdrawal and a distribution using a quasitwodimensional quasirectification model,
Based on the onedimensional quasirectification model for the river data, the water depth average velocity and the water depth of the vertical section of the whole section of interest are calculated, and the total amount of sediment per unit width of the longitudinal section is calculated using the calculated water depth average velocity and the water depth A onedimensional quasirectified model calculation unit for calculating the vertical lower elevation according to the onedimensional quasirectification model using the calculated total similar amount per longitudinal unit width;
A lateral flow velocity distribution calculation section for calculating a lateral flow velocity distribution for each of a plurality of transverse unit width zones in accordance with a transverse distribution method (LDM) using an average flow velocity, a depth of water, ;
A lateral similarity distribution calculation unit for calculating a distribution of the lateral direction similarity amount for each of all the unit width zones based on the lateral flow velocity distribution; And
And a lateral river bed variation calculation unit for calculating the lateral river bed fluctuation based on the lateral direction similarity distribution.
The transverse river bed variation calculation unit may calculate,
May be operable to calculate deformation of the bed slope using an activity algorithm.
According to the method and apparatus for stream leaving and dumping analysis using the quasitwodimensional quasirectification model of the present invention, it is possible to provide accuracy that does not fall far below that of the unsteady flow equation model with much less computational complexity than the unsteady flow equation.
According to the method and apparatus for stream leaving and distribution analysis using the quasitwodimensional quasirectification model of the present invention, prediction results over a long period of time can be provided.
According to the method and apparatus for stream leaving and dumping analysis using the quasitwodimensional quasirectification model of the present invention, it is possible to provide the lateral distribution of the depthofthestream mean velocity, the bed shear stress, the lateral shear and the river terrain.
According to the method and apparatus for stream leaving and distribution analysis using the quasitwodimensional quasirectification model of the present invention, it is possible to predict a river bed variation over a much longer period with a simulation system having the same calculation capability, And it is possible to simulate river bed variations under more varied conditions within the same cost and time.
The effects of the present invention are not limited to those mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the following description.
FIG. 1 is a flowchart illustrating a method of analyzing a stream leaving and applying a quasitwodimensional quasirectification model according to an embodiment of the present invention.
FIG. 2 is a graph showing the result of a river quenching and dumping analysis using a quasitwodimensional quasirectification model according to an embodiment of the present invention. As shown in FIG. 2, These are graphs comparing predicted and measured results.
FIG. 3 is a block diagram illustrating an apparatus for analyzing a stream leaving and applying a quasitwodimensional quasirectifier model according to an embodiment of the present invention.
For the embodiments of the invention disclosed herein, specific structural and functional descriptions are set forth for the purpose of describing an embodiment of the invention only, and it is to be understood that the embodiments of the invention may be practiced in various forms, The present invention should not be construed as limited to the embodiments described in Figs.
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals are used for the same constituent elements in the drawings and redundant explanations for the same constituent elements are omitted.
FIG. 1 is a flowchart illustrating a method of analyzing a stream leaving and applying a quasitwodimensional quasirectification model according to an embodiment of the present invention.
Referring to FIG. 1, in the step S11, a method of analyzing a stream leaving and distributing with a quasitwodimensional quasirectification model will be described with respect to a given river bed data including an initial river terrain, a flow rate, a sediment particle size, a sediment inflow amount, Based on the 1D quasisteady model, the cross section depth averaged velocity and the longitudinal hydraulic depth of the vertical section of the entire area of interest are calculated.
Onedimensional semirectification models are commonly used to produce longterm morphological changes in streams. The onedimensional quasirectification model neglects the timedependent change in the flow equation because the characteristic time of the bed elevation is very long compared to the flow change in simulating the change of the bed shape by the water flow. Quasisteady is based on assumptions.
Specifically, the onedimensional quasirectification model computed in step S11 may include a 1D continuity equation for the flow of equation (1) and a momentum equation of equation (2).
In the equations (1) and (2), x is the longitudinal direction, t is the time, q is the unit discharge, U _{A} is the depth average velocity, H _{A} is the depth of the section, g is the gravitational acceleration,
Is the bed elevation, and C _{f} is the flow resistance coefficient.Since the quasirectified model can be derived from the onedimensional shallow water equation, assuming that the characteristic time of the lower elevation is much larger than the characteristic time of the flow, It is difficult to apply it in cases such as the collapse of a dam or the flooding of a dam.
On the other hand, the above onedimensional quasirectified model has more bed sediment conservation equations like the Exner equation. In order to calculate this, the total sediment load per unit width.
Subsequently, in step S12, the total similarity amount per unit width of the longitudinal section is calculated using the calculated depthaverage flow velocity and the section depth.
Specifically, the total amount of similarity per unit width can be calculated using, for example, the EngelundHansen equation as shown in Equation (3) or the Yang equation as shown in Equation (4).
Where q _{s} is the total amount of sediment per unit width to be calculated, R is the submerged specific gravity, d _{50} is the median size of the sediment particles,
Is shear stress, C _{f} is bed resistance and g is gravitational acceleration.However, the EngelundHansen equation of Equation (3) may not be desirable when the particle diameter is 0.15 mm.
Most of the similarity calculation equations do not take the wash load into consideration, and the existence of trilys affects the fluid viscosity, sediment fall velocity and specific weight of sediment There are many cases where it can not be ignored. In such a case, the Yang equation of Equation (4) can be used. The Yang equation below is an equation for sedimentladen fluid flow with a high concentration of trichloride.
Where C _{s} is the fluxbased mass concentration, a _{1} and a _{2} are the empirical parameters,
Is the specific weight of sediment in sedimentladen flow, Is the specific weight of sediment, Is the descent rate of sediment.In step S13, the longitudinal bed elevation is calculated according to the onedimensional quasirectification model using the calculated total amount per longitudinal unit width.
Specifically, the longitudinal lower elevation can be calculated using Equation (5).
here,
Is bed elevation, t is time, Is the porosity of the bed material, Is the sediment load per unit width, and x is the longitudinal distance from the upstream to the corresponding point.Through the abovedescribed steps S11 to S13, the average flow velocity, depth, and bed elevation of the longitudinal vertical section through the longitudinal onedimensional quasirectification model are calculated.
Next, in step S14, the average lateral velocity of the vertical vertical section, the depth of the vertical section, and the height of the vertical section are used to calculate the transverse distribution width Direction flow velocity distribution.
The lateral distribution method of flow rate is derived independently from each other by Shiono and Knight and Walker et al. In the case where the flow rate and the water level are determined at one point of a river, the lateral unit It is a technique to obtain the flow rate per square meter.
The modified transverse velocity distribution method suitable for the present invention is expressed by the following Equation (6).
Where x is the longitudinal distance, y is the lateral distance,
G is the gravitational acceleration, H is the depth of water, S _{x} is the bed slope in the x direction, Is the bed shear stress, B _{g} is the shear stress S _{y} is the ydirection slope of the bed, Is the depthaveraged lateral shear stress, Is the term due to secondary currents.Equation (6) is a governing equation that distributes the total discharge in the lateral direction according to the stream topography and the hydrodynamics. Equation (6) can be discretized by applying a centered finite difference scheme with freeslip boundary conditions on each side for each unit width region. The resulting solution of the nonlinear equations can be calculated using the NewtonRaphson method.
On the other hand,
Can be given by the following Equation (7).
here
Is the density of water, f is the friction factor of DarcyWeisbach, and U _{d} is the depthaveraged velocity in the x direction.Also, the depthaveraged transverse shear stresses occurring between each transverse water column
Can be given by the following equation (8).
here,
Is the Reynolds stress due to fluctuating velocities. According to the Eddy Viscosity Concept, transverse shear stress Can be rewritten as Equation (9).
here
Is the eddy viscosity, which determines the shear stress between several weeks due to the difference in flow velocity, Is the density of water and U _{d} is the depth average velocity in the x direction.Finally, the secondary term of equation (6)
Is defined as < EMI ID = 10.0 >
here,
And Are the timeaveraged xdirection and ydirection components of the flow velocity, z is the vertical distance and H is the water depth, Is the density of water.Subsequently, in step S15, the distribution of the transverse similar amount is calculated for each of all the unit width zones based on the lateral flow velocity distribution.
Similar particles deposited in the slope of the bed can be retained or collapsed by a balance or imbalance between forces such as drag, gravity, Coulomb resistive force. This transport of bedload can be calculated by the vectorial formula of Kovacs and Parker according to the following equation (11).
here,
Is the vectorial volume bedload transport rate of bed sediment per unit width per unit width, Is the mean particle velocity, Lt; / RTI > Is the volume fraction of sediment in the total volume Is the height of the bedload layer from the bed.On the other hand, in step S16, the lateral river bed variation is calculated based on the lateral direction similarity distribution.
Specifically, the lateral river bed fluctuation can be obtained by calculating the lateral lower elevation as shown in the following equation (12).
here,
T is the time, The porosity of the bed material, Is the total amount of similarity per lateral unit width, and y is the lateral distance.Next, in step S17, a deformation of the bed slope is calculated using a sliding algorithm.
Specifically, the activity algorithm is Menendez, A.N., Laciana, C.E., Garcia, P.E. (2008) "An integrated hydrodynamicsedimentologicmorphologic model for the evolution of alluvial channels cross sections ", Engineering Applications of Computational Fluid Mechanics, Vol. 2, No. 4, pp. 411426.
Steps S11 to S17 may be repeated according to the flow of time.
The quasitwodimensional quasirectification model of the present invention can be implemented in a computer because it consists of calculation of a number of equations based on numerical data and mathematical models.
The operation procedure of implementing the method of analyzing the stream leaving and breaking by applying the quasitwodimensional quasirectifying model of the present invention will be briefly described. First, at a specific point in time, backwater equations such as Equations 1 and 2, The water surface elevation, sectionaveraged velocity, and bed elevation change are calculated for each longitudinal measurement point by calculating the equation of bed reservoir as shown in Equation (5).
Then, for each measurement point, the solution is calculated by the equation (2) with the surface elevation obtained from the solution of the multiple equation. Typically, the total discharge obtained by summing the similar amounts per unit volume calculated through the lateral distribution method is not equal to the actual total flow. The flow rate per unit width in each vertical cross section is obtained by distributing the actual flow rate, assuming that the flow rate distribution across the cross section will be similar to the distribution under a uniform flow condition.
The above calculation procedure is repeated so that the bed similarity can be distributed along the width direction of each measurement point. That is, the total bed profile is estimated using the shear flow rate averaged around the cross section. The unit bed similarity is then predicted by the transverse distribution method. In general, the sum of the unit bed weights in the width direction may not be equal to the total bed variation. The total bed profile is distributed in each vertical section under the above assumptions.
Finally, changes in stream shape are calculated taking into account bedload transport and sliding, assuming that the water flow is uniform within each operating range.
FIG. 2 is a graph showing the result of a river quenching and dumping analysis using a quasitwodimensional quasirectification model according to an embodiment of the present invention. As shown in FIG. 2, This is a graph comparing predicted and measured results of the terrain.
Xiao Lang Dam is a dam constructed in the main stream of the Yellow River, 128.42 km downstream from the Henan Province of China, and has an average annual flow of 400 × 10 ^{6} ㎥, 13.47 × ^{10 9} tons per year, and 12 major tributaries .
2, (a), (b) and (c) of FIG. 2 are graphs comparing predicted results of lateral river terrain obtained in 2003, 2004 and 2006, respectively, (Denoted as initial bed) is indicated by a thick black solid line, and a black solid line with a measured result (indicated as surveyed) and a predicted result according to the existing GSTARS4 simulation method (indicated by Ahn (2011) And the prediction result (represented by the present study) according to the quasitwodimensional quasirectification model of the present invention is indicated by a thin red solid line.
The river topography of October, 2003, due to the flood in August of that year, actually produced a huge amount of sediment upstream of the dam. The quasitwodimensional quasirectification model of the present invention also showed a prediction result sufficiently close to the actual measurement result, Compared to the widely used GSTARS4 simulation method prediction results.
The river topography of October 2004 was moved to the direction of the dam due to the erosion of sediment deposited in the previous year. The quasi  two  dimensional quasi  rectification model of the present invention showed close prediction results in some sections of the experimental results. It is necessary to consider that there is a large error in the prediction result of the existing GSTARS4 simulation method in the section where the model of the present invention has a large error.
The stream topography of October 2006 showed a sedimentation over a long section as a whole, and the quasitwodimensional quasirectification model of the present invention also showed a prediction result close enough to the actual measurement results, There is no difference compared to the simulation results.
FIG. 3 is a block diagram illustrating an apparatus for analyzing a stream leaving and applying a quasitwodimensional quasirectifier model according to an embodiment of the present invention.
Referring to FIG. 3, the stream withdrawal and distribution analyzer 30 applying the quasitwodimensional quasirectification model includes a onedimensional quasirectification model calculation unit 31, a lateral flow velocity distribution calculation unit 32, Section 33, a lateral river bed variation calculation section 34 and a database 35. [
The database 35 stores the given bedside data including the initial river terrain, the flow rate, the sediment particle size, the sediment inflow amount, the tributary flow, etc. and includes a onedimensional quasirectified model calculation unit 31, a lateral flow velocity distribution calculation unit 32, The lateral similarity distribution calculating section 33, and the lateral river bed variation calculating section 34, respectively.
The onedimensional quasirectification model calculator 31 calculates the depthaveraged flow velocity and the crosssectional water depth of the vertical section of the entire interest area based on the onedimensional quasirectification model with respect to the bedside data, and uses the calculated depth , And the vertical bottom height is calculated according to the onedimensional quasirectification model using the calculated total amount per unit width of the longitudinal direction calculated.
Specifically, the onedimensional quasirectification model calculated by the onedimensional quasirectification model calculation unit 31 may include a onedimensional continuity equation related to the flow of the equation (1) and a momentum equation of the equation (2).
Specifically, the total amount of similarity per unit width can be calculated using the EngelundHansen equation as shown in Equation (3) or the Yang equation as shown in Equation (4).
Specifically, the longitudinal lower elevation can be calculated by using the bed soil storage equation as shown in Equation (5).
The transverse flow velocity distribution calculation section 32 calculates the transverse flow velocity distribution for each of the plurality of transverse unit width zones according to the transverse distribution method (LDM) using the average flow velocity, depth and lower elevation of the calculated vertical vertical cross Obtain the distribution.
The flow velocity distribution method modified to be suitable for the present invention is explained by the abovedescribed Equations (6) to (10).
The lateral similarity amount distribution calculation unit 33 calculates the distribution of the lateral direction similarity amount for each of all unit width regions based on the lateral direction flow velocity distribution.
The transfer of bed similarity can be calculated by the vector formula of Kovacs and Parker according to the abovementioned Equation (11).
The lateral riverbed variation calculation unit 34 calculates the lateral riverbed variation based on the lateraldirection similarity distribution.
More specifically, lateral lateral bed fluctuation can be obtained by calculating lateral lateral elevation as shown in Equation (12) above, and deformation of bed slope can be calculated using an activity algorithm such as Menendez et al.
In this manner, according to the present invention, the river level fluctuation in the lateral direction is also calculated for each measurement point together with the river level variation calculated in the longitudinal direction along the center line of the river, thereby realizing a twodimensional simulation Instead, it is possible to simulate bed deposition twodimensionally close to a twodimensional simulation.
Using this quasitwodimensional method according to the present invention, a simulation system with the same computation capability can be used to predict river changes over a much longer period of time, or the cost of predicting river changes can be reduced if the same prediction period is used , Or simulate river changes under more varied and precise conditions within the same cost and processing time.
It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. It will be understood that variations and specific embodiments which may occur to those skilled in the art are included within the scope of the present invention.
Further, the apparatus according to the present invention can be implemented as a computerreadable code on a computerreadable recording medium. A computerreadable recording medium includes all kinds of recording apparatuses in which data that can be read by a computer system is stored. Examples of the recording medium include ROM, RAM, optical disk, magnetic tape, floppy disk, hard disk, nonvolatile memory and the like. The computerreadable recording medium may also be distributed over a networked computer system so that computer readable code can be stored and executed in a distributed manner.
30 A quasitwodimensional quasirectification model is applied to river discharge and discharge analysis
31 Onedimensional semirectification model calculation unit
32 lateral flow velocity distribution calculation section
33 Transverse direction similarity distribution calculation unit
34 transverse direction bed variation calculation unit
35 databases
Claims (18)
 A computerized quasi  two  dimensional quasi 
The computer comprising:
(a) Based on a onedimensional quasirectification model for given bedside data including initial stream topography, flow, sediment particle size, sediment flow, tributaries, etc., Calculating a depth of water;
(b) calculating a total amount of similarity per unit width of the longitudinal section by using the calculated water depth average velocity and the depth of the section;
(c) calculating the longitudinal undersurface height in accordance with the onedimensional quasirectification model using the calculated total amount per longitudinal unit width;
(d) calculating the lateral flow velocity distribution according to the lateral distribution method using the average flow velocity, water depth, and bottom height of the vertical longitudinal section;
(e) calculating a lateral similarity distribution based on the lateral flow velocity distribution; And
(f) calculating the transverse river bed variation based on the lateral direction similarity distribution, wherein the quasitwodimensional quasirectification model is applied to the river sedimentation and distribution analysis.  2. The method according to claim 1, wherein (b) calculating a total similarity amount per unit width of the longitudinal cross
And calculating a solution of the solution,
Where q _{s} is the total amount of sediment per unit width to be calculated, R is the submerged specific gravity, d _{50} is the median size of the sediment particles, Is a nondimensional shear stress, C _{f} is a bed resistance coefficient, and g is a gravitational acceleration.  2. The method according to claim 1, wherein (b) calculating a total similarity amount per unit width of the longitudinal cross
And calculating a solution of the solution,
Where C _{s} is the fluxbased mass concentration, a _{1} and a _{2} are the empirical parameters, Is the specific weight of sediment in sedimentladen flow, Is the specific weight of sediment, Is a descending rate of the sediment. The method of analyzing the stream sedimentation and distribution using the quasitwodimensional semirectification model.  The method of claim 1, wherein (c)
The following equation
And calculating a solution of the solution,
here, Is bed elevation, t is time, Is the porosity of the bed material, Is the sediment load per unit width, and x is the longitudinal distance from the upstream to the corresponding point. The quasitwodimensional quasirectification model is applied to the river sedimentation and distribution analysis.  The method of claim 1, further comprising: (d) calculating a lateral flow velocity distribution in accordance with the lateral distribution method
The following equation
And calculating a solution of the solution,
Where x is the longitudinal distance, y is the lateral distance, G is the gravitational acceleration, H is the depth of water, S _{x} is the bed slope in the x direction, Is the bed shear stress, B _{g} is the shear stress S _{y} is the ydirection slope of the bed, Is the depthaveraged lateral shear stress, Is a term due to secondary currents. The quasitwodimensional quasirectification model is applied to the river sedimentation and distribution analysis.  The method of claim 5, wherein the depthaveraged transverse shear stress Is expressed by the following equation
Lt; / RTI >
here Is the eddy viscosity, which determines the shear stress between water columns due to the difference in flow velocity, Is the density of water and U _{d} is the depth average velocity in the x direction.  The method according to claim 5, Is expressed by the following equation
Lt; / RTI >
here, And Are the timeaveraged xdirection and ydirection components of the flow velocity, z is the vertical distance and H is the water depth, Is a density of water. The method of analyzing the drainage and distribution of streams by applying the quasitwodimensional quasirectification model.  The method according to claim 1, further comprising repeating steps (a) through (f) for each time unit for a longterm simulation, wherein the quasitwodimensional quasirectification model is applied.
 The method according to claim 1,
The method of claim 1, further comprising: (g) calculating a deformation of the bed slope using the activity algorithm after the step (f).  A computer program stored on a recording medium for executing each step of a stream leaving and breaking analysis method applying a quasitwodimensional quasirectifying model according to any one of claims 1 to 9 to a computer.
 Based on the onedimensional quasirectification model for the river data, the water depth average velocity and the water depth of the vertical section of the whole section of interest are calculated, and the total amount of sediment per unit width of the longitudinal section is calculated using the calculated water depth average velocity and the water depth A onedimensional quasirectified model calculation unit for calculating the vertical lower elevation according to the onedimensional quasirectification model using the calculated total similarity per unit length in the longitudinal direction;
A lateral flow velocity distribution calculation section for calculating a lateral flow velocity distribution for each of a plurality of transverse unit width zones in accordance with a transverse distribution method (LDM) using an average flow velocity, a depth of water, ;
A lateral similarity distribution calculation unit for calculating a distribution of the lateral direction similarity amount for each of all the unit width zones based on the lateral flow velocity distribution; And
An apparatus for analyzing river sedimentation and distribution using a quasi  two  dimensional quasi  rectification model including a lateral river bed variation calculation unit for calculating a lateral river bed variation based on a lateral direction similarity distribution.  [Claim 12] The method of claim 11, wherein the onedimensional quasirectification model calculator calculates a total amount of similarity per unit width of the longitudinal cross
Lt; RTI ID = 0.0 >
Where q _{s} is the total amount of sediment per unit width to be calculated, R is the submerged specific gravity, d _{50} is the median size of the sediment particles, Is a nondimensional shear stress, C _{f} is a bed resistance coefficient, and g is a gravitational acceleration.  [Claim 12] The method of claim 11, wherein the onedimensional quasirectification model calculator calculates a total amount of similarity per unit width of the longitudinal cross
Lt; RTI ID = 0.0 >
Where C _{s} is the fluxbased mass concentration, a _{1} and a _{2} are the empirical parameters, Is the specific weight of sediment in sedimentladen flow, Is the specific weight of sediment, Is a descending rate of the sediment, and a quasitwodimensional quasirectification model is applied to the river sedimentation and distribution analysis apparatus.  [12] The method of claim 11, wherein the onedimensional quasirectification model calculator calculates the vertical low
Lt; RTI ID = 0.0 >
here, Is bed elevation, t is time, Is the porosity of the bed material, Is a sediment load per unit width, and x is a longitudinal distance from the upstream to the corresponding point. A quasitwodimensional quasirectification model is applied to the river sedimentation and distribution analysis.  [12] The method of claim 11, wherein the transverse flow velocity distribution calculation unit calculates a transverse flow velocity distribution according to the transverse distribution method,
Lt; RTI ID = 0.0 >
Where x is the longitudinal distance, y is the lateral distance, G is the gravitational acceleration, H is the depth of water, S _{x} is the bed slope in the x direction, Is the bed shear stress, B _{g} is the shear stress S _{y} is the ydirection slope of the bed, Is the depthaveraged lateral shear stress, Is a term due to secondary currents. The quasitwodimensional quasirectification model is applied to the river discharge and discharge analysis.  16. The method of claim 15, wherein the depthaveraged transverse shear stress Is expressed by the following equation
Lt; / RTI >
here Is the eddy viscosity, which determines the shear stress between water columns due to the difference in flow velocity, Is the density of water and U _{d} is the depthaveraged velocity in the x direction.  16. The method of claim 15, Is expressed by the following equation
Lt; / RTI >
here, And Are the timeaveraged xdirection and ydirection components of the flow velocity, z is the vertical distance and H is the water depth, Is a density of water. A quasitwodimensional quasirectification model is applied to the river sedimentation and distribution analysis.  12. The apparatus according to claim 11, wherein the lateral river
And the operation algorithm is used to calculate the deformation of the slope of the river bed.
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CN106846475A (en) *  20170208  20170613  长江水利委员会长江科学院  A kind of river historical Appearance digital restoration method 
CN107703741A (en) *  20170831  20180216  上海电力学院  Robot motion's system identifying method based on quasimode type calibration Kalman filtering 

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assessment of reservoir sedimentation using quasi two dimensional model(advances in river sediment research, 2013) * 
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CN106846475A (en) *  20170208  20170613  长江水利委员会长江科学院  A kind of river historical Appearance digital restoration method 
CN107703741A (en) *  20170831  20180216  上海电力学院  Robot motion's system identifying method based on quasimode type calibration Kalman filtering 
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