ABSTRACT
This paper is intended as a contribution towards the development of better predictors of the geometric characteristics of alternate bars. The specific objective of the paper is to introduce a new equation for alternate bar length. It is assumed that the bars are formed under a steady and uniform flow; the bed is flat at the beginning of the experiment; the stage of interest is that where bars have grown to their fully developed state. The present equation is derived on the basis of dimensional considerations and all the data available to the authors; bars produced under different regimes of the turbulent flow are treated separately. Accordingly, the equation takes different forms depending on the flow regime. It is shown that the present equation produces better estimates of bar length than previous equations for rough turbulent flows as well as flows in the transitional regime of turbulent flow, with a marked improvement for the case of the transitional regime.
