Introduction of New Flow Resistance Parameter for the Study Coefficients of Vertical Velocity Distribution

Abstract

Validity of log-law distribution of velocity in vertical section for alluvial channel under different localized bed and flow conditions is studied in this paper. In this study a new dimensionless parameter, Hari’s Number (P_h), whose value is to be taken as Q/νh, is proposed to relate the same with numerical coefficients of log-law distribution. It was found that the values of numerical coefficients could satisfactorily be correlated to the proposed indicators P_h. Value of Y (additive numerical coefficient) increases with increase in value of P_h. At lower discharge and lower depth, the value of coefficient of determination is seen to decline, inferring that for lower P_h values, the velocity distribution is more random.