Probability density distribution of bedload 3-D velocity

The probability density distribution of bedload particles´ three dimensional velocity components was studied by experiments. Ten runs of tests with different particle diameter, specific gravity and flow slope were performed, and the 3-D velocity components were measured by a Three Dimensional Particle Tracking Velocimetry (3D PTV) system. The analysis results of experimental data showed that the probability density distribution of bedload particles´ velocities approximately took on the normal distribution, and the particle diameter and specific gravity did not exhibit considerable effects on the average characteristics of probability density distribution. The deflection coefficient of longitudinal velocity component increased with the increase in flow slope.