Stationary Solitary Waves in Turbulent Open-Channel Flow: Analysis and Experimental Verification

Two-dimensional turbulent free-surface flow with Froude numbers close to 1 is considered. The roughness of the bottom of the channel is allowed to vary with the space coordinate, leading to small variations in the bottom friction coefficient. In a predecessor of the present paper, an extended Korteweg-deVries (KdV) equation for the surface elevation was derived by means of an asymptotic analysis which is free of turbulence modeling. The steady-state version of the extended KdV equation has solutions that describe stationary solitary waves. In the present paper, previous results of the analysis are extended with the aim of providing a basis for the experimental investigations. A comparison of measured surface elevations with theoretical predictions is shown, and possible sources of small discrepancies are discussed. In an appendix, the structure of solutions that describe solitary waves with a tail is investigated. (C) 2015 American Society of Civil Engineers.