Author: FAN Jia-hua (China Institute of Water Resources and Hydropower Research, Beijing 100048, China)

Abstract: By analyzing the author’s and other researchers’test data of turbid density currents, it was found that the entrainment coefficient of turbid currents was similar to that of saline current when the Froude number exceeded 1. Analyses showed that when Richardson Number Ri =0.6-0.8, there is no entrainment to occur. While for small slopes, due to turbidity current carrying fine sediment particles, a small part of water seeped from the lower layer into the upper layer, resulting in so called negative entrainment. An empirical relationship between water entrainment coefficient and Richardson Number for turbid density current is developed by using experimental data obtained in test flumes of steep and mild bottom slopes. This curve can be used for the calculation of density current velocity and interface elevation variation in longitudinal direction.

Key words: Turbid density current; density current; interfacial wave breaking; density current; water; entrainment coefficient of turbid density current

Published in: Journal of Hydraulic Engineering, Vol. 42, No. 1, 2011

Article ID: 0559-9350 (2011) 01-0019-08