Comparison of Flow Characteristics in a Physical Model with 1D, Quasi-2D, and 2D Numerical Models in a River Reach

Document Type : Original Article

Authors

1 Associate Professor of River Engineering, Urmia University, Urmia, Iran

2 M.S Graduate, Hydraulic Structures, Urmia University, Urmia, Iran

Abstract

Numerical models are being used widely in river engineering projects. However, the reliability of these models, minimum field data requirement, and the optimal computational processes are of major concern. This study compares the simulated steady flow parameters from a well-known numerical models with that of a true river physical model. A fixed-bed model is developed for the nazloo river, IRAN, with horizontal scale of 1:100 and vertical scale of 1:20. Results from HEC-RAS (1D), BRI-STARS (quasi 2D), and FAST-2D (2D) were compared for corresponding flow parameters under similar initial and boundary conditions. This was made for five different flows in three sub-reaches along the river (i.e. downstream of a bridge, bridge reach, upstream of the bridge). The best adapted results were produced by HEC-RAS. BRI-STARS and FAST-2D models took the next ranks respectively. the averaged predictive errors were rated 1.8, 2.2, and 5.5 percent for water surface elevations and 10.2, 9, and 12.6 percent for mean velocities, respectively. The application of each model is recommended in river projects subject to the inclusion of the degree of certainties provided by the present study

Keywords

References

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Iran-Water Resources Research
Volume 2, Issue 3
June 2007
Pages 78-89

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History

  • Receive Date: 19 February 2006
  • Revise Date: 02 December 2006
  • Accept Date: 14 March 2007

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