Abstract:The three-dimensional movements of bed-load particles in an open channel with different grain diameters and different specific gravities under the conditions of different hydraulic gradient are measured by means of particle tracking velocimetry (PTV) technique. The average movement characteristics of the particles are analyzed by statistics. The results show that the longitudinal average velocities of the particles neither agree with the law suggested by Einstein nor obey the law assumed by Bagnold. Einstein’s law is that the particle velocity is equal to 11.6 times of shear velocity, and the Bagnold’s law assumes the velocity equal to the difference between flow velocity at corresponding water depth and settling velocity of particle. Two formulas for determining the velocity of particle in the forms of expression given by Einstein and Bagnold are obtained according to the statistical results of experimental data, respectively.
出版日期: 2009-12-05
引用本文:
. Experimental study on average movement characteristics
of bed-load particles[J]. Front. Struct. Civ. Eng., 2009, 3(4): 435-439.
Limo TANG, Xingkui WANG, . Experimental study on average movement characteristics
of bed-load particles. Front. Struct. Civ. Eng., 2009, 3(4): 435-439.
Einstein H A. The bed load function for sediment transportation in open channelflows. Technical Bulletin/ United StatesDepartment of Agriculture, 1950, 1026: 71
Bagnold R A. The nature of saltation of bed load transport in water. Proceedings of the Royal Society London, 1973, 332A: 473―504
Muste M, Yu K, Fujita I, Ettema R. Two-phaseversus mixed-flow perspective on suspended sediment transport in turbulentchannel flows. Water Resources Research,?2005,?41(10): W10402 doi: 10.1029/2004WR003595
Tang Limo, Yu Mingzhong, Liu Chunjing, Wang Xingkui. The developmentand elementary application of 3-D partricle tracking velocimetry. Journal of Hydraulic Engineering,??2006, 37(11): 1378―1383 (in Chinese)