Investigation of Longitudinal Dispersion Coefficient in rivers

Document Type : Original Article

Authors

1 PhD student, Dept. of Water Eng., College of Agric., Isf. Univ. Tech, Isfahan, Iran

2 Assoc. Prof., Dept. of Water Eng. College of Agric., Isf. Univ. Tech., Isfahan, Iran

Abstract

 
Over the course of recent decades, agricultural and industrial activities have led to a considerable pollution in rivers. To control the river pollution level, the waste water discharge should be regulated. Pollutions have been dispersed in longitudinal, lateral, and vertical direction. The longitudinal dispersion of pollutants in river is important. In this study, a comprehensive equation was proposed for longitudinal dispersion coefficient using dimensional analysis. Dimensional and statistical analysis indicated that longitudinal dispersion coefficient depends on roughness coefficient and the ratio of width to depth of river. Sensitivity analysis indicated that roughness coefficient had the highest effect on longitudinal dispersion coefficient. The proposed methodology is a new approach to estimate dispersion coefficient in streams and can be implemented into mathematical models of pollutant transfer. 

Keywords

References

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Iran-Water Resources Research
Volume 7, Issue 1
July 2011
Pages 59-66

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History

  • Receive Date: 28 February 2009
  • Accept Date: 16 March 2011

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