Generalized study of erosion by circular horizontal turbulent jets

Experimental data on erosion by circular wall jets from thirteen sources including the present experimental study were compiled and analyzed. The present experimental study consisted of circular air jets on a bed of canola seeds and circular water jets on sand and gravel beds. The compiled data, consisting of over 350 experiments, cover wide ranges of flow submergence, jet sizes and velocities, bed material size, relative channel width and relative density difference. Similarity of the scour hole was examined both in the unsteady and asymptotic states by determining the ratios between the characteristic dimensions of the scour hole. The effect of jet submergence on the asymptotic characteristic dimensions of the scour hole was found to be pronounced when the densimetric particle Froude number F-o is greater than 10. The effect of elevating the jet outlet on scour depth was also investigated. Equations relating the asymptotic characteristic dimensions of the eroded bed to F-o have been proposed. The effects of the relative density difference on the characteristic dimensions of scour were addressed.