基于TELEMAC-2D模型的嫩江干流洪水模拟分析研究OA

Numerical modeling of river flood evolution plays a crucial role in flood risk management and disaster prevention strategies.However,the interaction of water flow over the wide-shallow river is complex,and the applicability and accuracy of traditional hydrodynamic models needs to be further explored.Wide-shallow main stem of the Nenjiang River is characterized by intricate riverbank formations and highly concentrated water management infrastructure.To address the above-mentioned issues,the Fulaerji-Jiangqiao stationof the Nenjiang River was selected as the study area,and high-resolution terrain and geomorphological datasets were utilized to depict the impact of topography and embankments within the river on water flow evolution.On this basis,a two-dimensional flood evolution simulation model of the selected study area was constructed by the TELEMAC-2D.The simulated discharges obtained from the TELEMAC-2D model were then discussed and compared with those from the MIKE21 model during the flood season.The results showed that the built TELEMAC-2D model had satisfactory performance on flood modelling.The simulated inundation area was consistent with actual flood coverage observed in the concurrent remote sensing imagery.Also,the modelling results could effectively reflect the water-blocking effects of inner embankments and local microtopography on flood routing within the river channel.For different flood events,the relative errors of the flood peak flow at the gauged stations were all less than 20%.Furthermore,the coefficient of determination between the simulated and measured discharge series for most flood events was above 0.9.The modelling results of the TELEMAC-2D model were comparable to those from the MIKE21 model.The simulated flood process sequences from these two models exhibited similar trends in flood onset and recession stages,and both were consistent with the measured flood hydrographs.Additionally,the floodplain flow threshold for the studied river reach was determined to be approximately 1 100 m³/s,and the model demonstrated satisfactory performance in modelling both floodplain and non-floodplain flood events of different magnitudes.The results indicated that the TELEMAC-2D model had satisfactory modelling capability and was suitable for flood routing in wide and shallow rivers.