Volume No. 7 Issue No.: 1 Page No.: 139-145 July-September, 2012

 

RIVER FLOW MODEL USING LINK NODE SCHEME

 

Thinakaran E.* and Jothiprakash V.

Department of Civil Engineering, Indian Institute of Technology Bombay, Powai, Mumbai (INDIA)

 

Received on : July 05,2012

 

ABSTRACT

 

The river flow models are the basic model for any pollutant transport and flood simulation in a river reach. Link node networks forms the basis for most of the river flow models. This complete-one dimensional hydrodynamic model simulates the dynamics of the water movements in the river and calculates the flow characteristics at each cross section during given time step. Due to unsteady flow in a given river reach, unsteady continuity equation and the complete solution methods are desirable to solve the one-dimensional momentum equation. In the present study an explicit finite difference numerical model has been developed using link node scheme with the objective of predicting the water surface elevation and velocity distributions simultaneously across the entire model domain. The developed model is then applied to Androscoggin river, USA and validated with the measured depth and velocity. The objective is accomplished by applying the one-dimensional equation of motion to the river reach to predict river velocity and the continuity equation at junctions to predict fluctuations in the water surface elevation. It is found that the simulated and observed depth coincides and there is no variation. However the variations in the simulated and observed velocity shows the unstable nature of explicit finite difference method, especially for higher time step and indicates that other numerical modeling techniques like implicit finite difference or finite element method is required to compute the velocity variation for unsteady flow.

 

Keywords : River flow, Link node scheme, Unsteady flow methods, Complete dynamic equation, Finite difference scheme

 

 

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