The model was applied to forecast the discharge into Hoa Binh reservoir in the flood season 2006. The difference of this connected hydraulic-hydrological model in comparison with the other hydrological models is using the complete Saint-Venant 1D to simulate flow in rivers. Results of verification of the model show that it is good enough for practice. | Vietnam Journal of Mechanics, VAST, Vol. 30, No. 3 (2008), pp. 149 – 157 FORECASTING THE DISCHARGE INTO HOA BINH RESERVOIR BY APPLYING THE CONNECTING MODEL MARINE - IMECH1D Nguyen Tien Cuong Institute of Mechanics, VAST, Vietnam Trinh Thu Phuong National center for Hydro Meteorological Forecasting Abstract. Da river is the biggest one of three rivers: Da , Thao and Lo which flow into Hong river, so calculating and forecasting correctly the discharge to Hoa Binh reservoir take an important role in managing the task of flood preventing in the Hong - Thai Binh river system. In this paper, a connected hydraulic-hydrological model is developed. The model was applied to forecast the discharge into Hoa Binh reservoir in the flood season 2006. The difference of this connected hydraulic-hydrological model in comparison with the other hydrological models is using the complete Saint-Venant 1D to simulate flow in rivers. Results of verification of the model show that it is good enough for practice. 1. THE COMBINED MODEL OF IMECH-1D AND MARINE The simulating hydraulic one dimension IMECH-1D programme pack was developed at Institute of Mechanics, Vietnam Academy of Science and Technology. It was close verified and applied to simulate the flood forecast for Hong-Thai Binh river system. The set of simulating hydrological programme MARINE was developed at Toulouse Institute of Fluid Mechanics, France. It was handed over to Institute of Mechanics within the framework of “FLOod Control Decision Support” (FLOCODS) project financed by European Community. The combined model of MARINE and IMECH-1D has a high ability to simulate discharge process of flow correctively. The Saint-Venant 1D equations [2] used in IMECH-1D are: ∂Ac ∂Q + = q, (1) ∂t ∂x ∂Z ∂Q ∂ Q2 + β + gA + Sf = 0, (2) ∂t ∂x A ∂x where: Q = Q(x, t) is discharge of the flow in the river section; Z = Z(x, t) is the water level in the river section; Sf is the friction slope; Ac is the cross-sectional area; q is .
