Simultaneous velocity measurements of gas-solid phases in eolian sediment transport by particle image velocimetry-planar laser induced fluorescence

In this study, a new method was presented to determine simultaneously the velocity fields of gas-solid phases in the eolian sediment transport by means of PIV and PLIF. The fluorescent seed particles were micro particles atomized from rhodamine B solution. The specific optical filters and the two CCD cameras were employed in the measurement. The cross correlation algorithm and the corresponding image processing technology were used in the processing of the resulting vector plots. The samples at the south edge of Taklimakan Desert were measured. The velocity fields of the two phases were obtained. The results show that the horizontal velocities of the both phases had approximate logarithm distributions in vertical direction at the upper part of the inferior boundary layer of airflow. With the decrease of height, the gradient of the wind speed near the bed surface decreased monotonically and there was a pit in each velocity profile curve of both phases. The deviations occurred at approximately uniform height for all samples. In addition, the horizontal velocities of both phases would change with the sand grain size.