ENTRAINMENT BY 2-DIMENSIONAL SPILL PLUMES

A simple model is proposed for estimating the mass entrainment into tw o-dimensional (20) free plumes. The model rests on the assumption that the entrainment into the curved section of a spilling plume is approx imately equal to the entrainment into a vertical free plume rising thr ough the same height. The model is shown to be in good agreement with measurements in several small-scale models. The measured entrainment c oefficient for the 20 plumes in the scale model studies, which had bee n determined from measurements of entrainment into the vertical portio n of those plumes, was found to be around C-m = 0.44, slightly below r ecently proposed values for unbounded 2D plumes. It is suggested that the observed deviations front the proposed model of measurements in tw o small-scale models of atria might have been caused by the relatively small size ol shape of those atria. (C) 1998 Published by Elsevier Sc ience Ltd. All rights reserved.