A Numerical Simulation Method of River Structure Flow Based on Finite Volume Method

Abstract

The invention discloses a finite volume method-based numerical simulation method for flow of river structures. Firstly, the planar geometric data of the river channel, the cross-sectional data of the river channel and the geometric dimensions of the structures are obtained. The channel is discretized with a one-dimensional finite volume unit, the hydraulic element values ​​are stored in the unit center, and the location of the structure is the unit interface. Calculate the amount of water passing through the structure interface in each time step according to the structure flow formula, and then use the method of source term processing to deduct and increase this part of water in the two upstream and downstream units adjacent to the interface, in order to ensure the calculated Continuity, using non-reflection boundary conditions to reconstruct the hydraulic element values ​​at the interface of the structure, and then calculate the numerical flux at the interface of the structure. The invention can accurately reflect the flow characteristics of each structure, while ensuring the accuracy and stability of the overall calculation of the one-dimensional river flow model, and provides a new solution for the structure flow treatment under the numerical framework of the one-dimensional finite volume method.

Description

technical field [0001] The invention relates to the field of water conservancy engineering, in particular to the field of flood control risk analysis, in particular to a numerical simulation method for flow of river structures based on a finite volume method. Background technique [0002] The so-called river channel structures refer to the structures in the river channel that have obvious influence on the water flow in the channel, such as weirs, barrages, bridges and culverts. In engineering practice, a one-dimensional mathematical model is usually used to simulate the movement of river flood water flow, but the flow state of the structure is extremely complex, and the control equations used in the one-dimensional model can no longer describe this complex flow state, and the structure is also These are known as singularities within the computational domain and require special treatment. In engineering practice, structures in river channels are very common. Therefore, wheth...

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Problems solved by technology

However, this kind of numerical format based on implicit finite difference does not have the ability to capture shock waves and deal with excessive flow regimes. When applied to some rivers with steep terrain and large slope changes, it often causes divergence of numerical solutions and even simulation failures. The problem

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