Evaluation of Sediment Transport Function Using Different Fall Velocity Equations

Study of sediment transport in river morphological problems requires proper relation to be established for the estimation of the terminal velocity, also known as fall velocity of particles. A large number of formulas have been developed by many researchers to determine fall velocity for particles size of various ranges. Present work aims to determine the applicability of the unit stream power equation of Yang (1979) for predicting total load transport rate using different fall velocity functions of Van Rijn (1984 b), Cheng (1997), Julien (1995) and Soulsby (1997) for a range of hydraulic parameters. Flume data of Wills et al. (1972) and Stein R.A. (1965) are used to analyse the Yang's total load function. Graphical representation of 152 data points and plot of observed and predicted total load transport for the selected data sets shows the scattering of value from the line of perfect fit within small range of errors of +_100% for the data sets of Stein R.A. (1965) and Wills et al. (1972) for all the selected fall velocity functions. Applicability of Yang's total load function is also verified using different statistical parameters such as mean square error, Root mean Square Error, Inequality coefficient and Discrepancy ratio. Citation: H.N. Prajapati, Pacific School of engineering and Technology, Surat; M.S.Shah ,Assist. Professor, Civil, GIDC Degree Engineering College, Abrama, Navsari; S. I. Waikhom ,Dr. S & S S Ghandhy Government Engineering College, Surat, Gujarat, India ; Dr. S. M. Yadav ,Sardar Vallabhbhai National Institute of Technology, Surat. "Evaluation of Sediment Transport Function Using Different Fall Velocity Equations." Global Research and Development Journal For Engineering : 564 - 568.