Simulation of the electrification of wind-blown sand

Particle-Laden Droplet-Driven Triboelectric Nanogenerator for Real-Time Sediment Monitoring Using a Deep Learning Method

Continuous information on the suspended sediment in the water system is critical in various areas of industry and hydrological studies. However, because of the high variation of suspended sediment flow, challenges still remain in developing new techniques implementing simple, reliable, and real-time sediment monitoring. Herein, we report a potential method to realize real-time sediment monitoring by introducing a particle-laden droplet-driven triboelectric nanogenerator (PLDD-TENG) combined with a deep learning method. The PLDD-TENG was operated under the single-electrode mode with a triboelectric layer of polytetrafluoroethylene (PTFE) thin film. The working mechanism of the PLDD-TENG was proved to be induced by liquid-PTFE contact electrification and sand particle-electrode electrostatic induction. Then, its performance was explored under various particle parameters, and the results indicated that the output signal of the PLDD-TENG was very sensitive to the sand particle size and mass fraction. A convolutional neural network-based deep learning method was finally adopted to identify the particle parameters based on the output signal. High identifying accuracies over 90% were achieved in most of the cases by the proposed method, which sheds light on the application of the PLDD-TENG in real-time sediment monitoring.

Charge-to-mass ratio of saltating particles in wind-blown sand

The electrification of sand particles plays an important role in aeolian events. In this paper, the charge-to-mass ratio vertical profiles of saltating particles in wind-blown sand were measured by a field experiments. By combining the results of field measurements with our previous wind-tunnel measurements, we discussed the factors affecting the charge-to-mass ratio of saltating particles. It reveals that the magnitude of the charge-to-mass ratio increases exponentially with height above the surface. In addition, the charge polarity of saltating particles depends on the relative size between saltating and creeping particles, and the magnitude of charge-to-mass ratio is determined by wind velocity and the relative size difference ratio between saltating and creeping particles.

Electrification of wind-blown sand: recent advances and key issues

In this paper, we summarize the recent advances on the electrification of wind-blown sand. Some of the outstanding questions, such as the interpretation of the electrification of wind-blown sand, measurements on and models of the features of the wind-blown sand E-fields, as well as their effect on the wind-blown sand flux and electromagnetic wave propagation, are reviewed. We end by highlighting the challenges that remain.