This paper describes an approach to construct an one- and quasi-two dimensional hydraulic model for the complex river network, including various hydraulic structures. The model is based on the numerical solution of the Saint-Venant equations for river branches, the continuity equation for storages, the equation for junction conditions of the confluences, tributaries, the equation for hydraulic structures between rivers and storage cells. | Vietnam Journal of Mechanics, NCST of Vietnam Vol. 24, 2002, No 3 (181 - 196) ON AN ONE- AND QUASI-TWO DIMENSIONAL LINKING HYDRAULIC MODEL FOR THE COMPLEX RIVER NETWORK-VALIDATION AND APPLICATION NGUYEN VAN HANH 1 , NGO HUY CAN 2 AND NGUYEN VAN DIEP 2 1 Institute for Water Resources Research, 271 Tay son street, Hanoi, Vietnam 2 Institute of Mechanics, 264 Doi can street, Hanoi, Vietnam ABSTRACT. This paper describes an approach to construct an one- and quasi-two dimensional hydraulic model for the complex river network, including various hydraulic structures. The model is based on the numerical solution of the Saint-Venant equations for river branches, the continuity equation for storages, the equation for junction conditions of the confluences, tributaries , the equation for hydraulic structures between rivers and storage cells. Cross sections are modeled as a combination of main and flood plain parts to simulate better the flow pattern. The calculating program has been ~eveloped, validated by test cases, proposed by European big hydraulic research laboratories and then applied to build a hydraulic model for the complicated Red-Thai Binh river network. 1. Introduction Free surface flow in a river delta is complicated and is investigated extensively last years. The flow can be simulated by one- or two-dimensional mathematical models [1-3], depending on the study purpose. However, two-dimensional models are expensive for large river deltas. In this case, the main technique is to use an one- and quasi-two dimensional approach [3], which can be rather cheaper both in calculating time and cost. In the one- and quasi-two dimensional approach the research area is considered as a combination of a river network and storage cells. Storage cells can exchange flow with rivers and with each other through hydraulic structures. In this paper an approach to construct an one- and quasi-two dimensional linking hydraulic model for the complex river network is presented. The .
