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| Wind erosion and numerical modelling on its electric field of bare soil over lands |
| Received:May 17, 2014 Revised:August 25, 2014 |
| View Full Text View/Add Comment Download reader |
| DOI：10.7511/jslx201503023 |
| KeyWord:wind erosion electric field gas-solid coupling numerical simulation |
| Author | Institution |
| 岳高伟 |
河南理工大学 土木工程学院, 焦作 |
| 许梦飞 |
河南理工大学 土木工程学院, 焦作 |
| 陆梦华 |
河南理工大学 土木工程学院, 焦作 |
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| Abstract: |
| Wind erosion is the serious disaster problem for agriculture and environment,so it needs insight into its mechanical mechanism to prevent and control effectively soil and related disasters.In this paper,granular flow dynamics model in bare lands,which is coupled with wind and soil particles,is suggested to describe the evolution process of wind erosion.And based on the theory of water ionization,the soil particles charged model is establish to reveal the particles charged during the collision process.Each charged soil particle can be look as a point charge,so the calculation model is given to simulate the characteristics of soil erosion electric field until its reaching a dynamic equilibrium.The numerical simulation results show that with the action of wind force,the soil particles roll or jump,and then they impact other soil particles on bare lands.During the wind erosion process,the wind provides continuously energy for moving soil particles,and the moving soil particles also weaken the wind,with the coupling the wind erosion reaches a dynamic stability in about 7 seconds.In the dynamic equilibrium the calculation result of soil erosion amount is mostly closed to the experimental results.And the quantity of wind erosion decreases exponentially with height,especially below 10cm height the soil erosion amount exceeds 90% of the total,which indicates that wind erosion is the particle transport phenomena near lands.During two soil particles collision process,charge transform of H3O+ and OH- causes the collision particles charged,and the larger soil particles positively charged,the smaller soil particles negatively charged.In different particles size intervals the change of the total electricity fluctuates with time,but the overall trend of electric quantity increases rapidly in the initial stage,and then decreases slowly until reaching a dynamic stability.The charged soil particles produce electric field,the electric field intensity is weak at the beginning and then gradually increases until wind erosion reaches stability,and the electric field intensity decreases with height.The study results indicate that it will be an important trend to consider the electric field in wind erosion,which provides a theoretical basis to establish more practical and comprehensive soil erosion model. |
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