Modeling of Air Flow and Sand Particles Emission around Low-Lying Hills Using Large Eddy Simulation

Document Type : Original Article

Authors

1 Department of Mechanical Engineering, University of Qom

2 Space Science and Earth Atmosphere Research Lab., Department of Mechanical Engineering, University of Qom

Abstract

The emission and distribution of dust particles are of the most important issues in the field of environmental studies. The transfer of dust particles is influenced by natural and environmental factors and always has destructive effects on the environment and especially on people's health. In present research, the numerical simulation of the emission of dust particles around low-lying hills has been done. The emission of dust particles is influenced by factors such as airflow velocity, environmental conditions, surface and also the type and structural characteristics of the particles. In order to accurately predict the flow field and investigate the way of dust particles emission, a numerical method based on the large eddy simulation has been used. Validation of the model was performed based on the comparison of simulation results with the laboratory data. It shows an appropriate accuracy for modeling based on the large eddy simulation. In the current research, the numerical simulation of fluid flow has been done with the Fluent module from the Ansys software package. The results of this research, including changes in the concentration of dust particles under the influence of factors such as airflow velocity and the diameter of the particles, have been presented and discussed. The results show an increase in the concentration of sand particles by reducing their diameter from 200 microns to 20 microns in this study. Also, the higher velocity of the inlet air flow into the computing domain, the lower the concentration of particles on the surface of the hill and its surrounding environment.

Keywords


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  • Receive Date: 11 August 2022
  • Revise Date: 19 October 2022
  • Accept Date: 28 February 2023
  • Publish Date: 20 February 2023