Study On Downstream Flood Simulation Of The Heihe Jinpen Reservoir

Flood disaster is one of the gravest and the most frequently natural disasters, it threatens people's life and property, also affects national economic construction.The Jinpen Key water conservancy project is the main water project of Jinpen diversion works of Xi'an, it's a large hydraulic project which gives priority to city water supply, gives consideration to irrigation, energy production, flood control, etc. There are multitudinous people, factories and agricultural production in downstream area of Jinpen reservoir. If rare flood takes place, it will hang over downstream area seriously.In this paper, HEC-RAS model, ArcView GIS and HEC-GeoRAS are put in use, design flood (P=1% ) and check flood (P=0.5%) of Jinpen reservoir are simulated, after reservoir regulating. Also, flood routing simulation in the downstream and downstream area is completed.This paper can be divided four parts, approximately:In the first part, several methods for flood routing simulation are sum up. The hydrology methods and hydraulic methods are mainly introduced. The hydrology methods' principles and characteristics are expounded, then hydraulic methods are introduced particularly, including main equations and computing procedures of the zero dimensional model, the one dimensional model and the two dimensional model. Related simulate software is introduced, including Delft3D, MIKE, SMS, HEC-RAS, etc.In the second part, principles and characteristics of a series of HEC models are introduced.In the third part, reservoir regulating for design flood (P=1%)and check flood (P=0.5%) of Jinpen reservoir is completed. Firstly, design flood is simulated by HEC-RAS, the main results are as follows:(1) Max. level of all crossections' water surface profiles, just in the simulating time.(2) Max. water surface profiles along flow path. (3) Max. flood flow velocities along flow path. (4) Stage～Flow～Time relationship of up and down crossectons. (5) All crossections' hydraulic properties.After that, based on the digital terrain model (DTM), check flood is simulated by HEC-RAS, under ArcView GIS3.2 (coupled HEC-GeoRAS), the main results are as follows:(1) The digital terrain model (DTM) of research area in river basin is developed. (2) Max. Level of all crossections' water surface profiles, just in the simulating time. (3) Max. water surface profiles along flow path. (4) Max. flood flow velocities along flow path. (5)A11 crossections' Stage～Flow relationship. (6) Stage～Flow～Time relationship of up and down crossections. (7) All crossections' hydraulic properties. (8) Max. flood inundated map in the simulating time and inundated maps according to each time.In the forth part, not only all the work in the paper is summarized, but further work is elaborated, then suggestions for HEC-RAS model are bring up.Based on the work of this paper, it demonstrates that the results of simulation are reasonable. At the same time, It may be of help for flood forecasting, planning to pullout people, disaster assessment, etc.