Sedimentary distribution of particles in Malan loess under wind power

Abstract

The distribution law of dust particles under the action of wind is of great significance for the transport and settlement of loess in ancient environment and the study of modern sand and dust on environmental pollution. Based on wind tunnel test, physical model and numerical simulation, the particle transport deposition process was studied, and the following conclusions were obtained through mutual verification: (1) The particle size information in wind tunnel test shows that the smaller the particle size is. (2) Through the physical model, it is deduced that the ideal transport distance of dust particles is inversely proportional to the second square of particle diameter, which is well verified by the experimental results in this paper; (3) In the experiment, the grain size distribution curve of sedimentary particles is bimodal, which is a strong proof that the source area of particles and the transport path are the same in the loess area; The curve is a right-sided curve of normal distribution, which is the same as the grain gradation curve of undisturbed loess in northwest China. We believe that the reason for this trend is the different deposition rates of coarse and fine particles. (4) In the numerical simulation, we observed the influence of rising wind and other conditions on the distribution of sedimentary particles, which has certain reference significance for the actual dust transport process.