Well-Balanced Scheme for Modeling Open-Channel and Surcharged Flows in Steep-Slope Closed Conduit Systems

作者：Leon Arturo S^*; Gifford Miears Christopher; Choi Yunji

来源：Journal of Hydraulic Engineering, 2013, 139(4): 374-384.

DOI：10.1061/(ASCE)HY.1943-7900.0000690

• Combined sewer system
• Finite-volume method
• Open-channel flow
• Storm water system
• Surcharged flow
• Transient flow
• Unsteady flow
• Well-balanced scheme

The model presented in this paper preserves lake at rest conditions in sloped prismatic conduits. These schemes are based on the two-governing equation model in which open-channel flows are simulated using the Saint-Venant equations and pressurized flows using the compressible water hammer equations. The model in this paper preserves lake at rest conditions (horizontal still water) regardless of the conduit slope, resolves moving jump discontinuities over dry beds in sloped conduits, and resolves small perturbations from steady states, even when adjacent to dry regions. The preserving steady-state capability of this model is of particular importance in continuous long simulations when the conduits are relatively steep (vertical bar S-o vertical bar %26gt; similar to 0.5%. Two main contributions are presented in this paper, namely, (1) a new method for water stage reconstruction is presented that preserves lake at rest conditions regardless of the pipe slope, and (2) a horizontal system of coordinates, instead of the commonly used inclined coordinate system, is used for facilitating the implementation of the proposed well-balanced scheme to complex systems. In the horizontal coordinate system, the cross section of a circular pipe becomes an ellipse. The hydraulic characteristics of an ellipse are presented. Good results are achieved in the test cases. DOI: 10.1061/(ASCE)HY.1943-7900.0000690.

• 出版日期2013-4