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Numerical and experimental study of granular piles when subjected to wind erosion
Tese de doutoramento em Engenharia Mecânica, no ramo de Aerodinâmica Industrial e Engenharia do Vento, apresentada ao Departamento de Engenharia Mecânica da Faculdade de Ciências e Tecnologia da Universidade de Coimbra ; The transport of soil particles by wind is of enormous relevance in a wide range of events from those related to agriculture (e.g., seed transport) to the formation and modification of the landscape. A classic example is sand dunes, which can be formed, moved, or entirely eroded due to aeolian processes. Still, aeolian transport of particles may cause serious damage in transportation, communications and severe environmental problems, such as the degradation of air quality due to dispersion of pollutants from stockpiles. The wind exposure will lead to the particles movement through several mechanisms, such as, suspension, creeping, saltation, and saltation bombardment. Consequently, the free surface will change over time due to entrainment and deposition phenomena. The main objective of this study is assessing the airflow characteristics over and around granular material complex three-dimensional piles when subjected to the wind erosion and its influence in the behavior of the free surface, as well as, in the sand emission rate. A literature review was made over the main subjects of interest to the present work, from the basics, such as granular material and aeolian transport mechanisms, to the key magnitudes involved in the wind erosion phenomena. Studies performed to calculate the dust emission from stockpiles are presented and reviewed along with the widely applied methodology from United States Environmental Protection Agency (USEPA). This methodology estimates the emission of particles from stockpiles only during specific erosion events, such as bursts, when in reality emissions occur in many other occasions. The present work offers the possibility of conducting the determination of emissions from stockpiles along time; this approach makes viable to follow the time-dependent evolution of the ...
Numerical and experimental study of granular piles when subjected to wind erosion
Tese de doutoramento em Engenharia Mecânica, no ramo de Aerodinâmica Industrial e Engenharia do Vento, apresentada ao Departamento de Engenharia Mecânica da Faculdade de Ciências e Tecnologia da Universidade de Coimbra ; The transport of soil particles by wind is of enormous relevance in a wide range of events from those related to agriculture (e.g., seed transport) to the formation and modification of the landscape. A classic example is sand dunes, which can be formed, moved, or entirely eroded due to aeolian processes. Still, aeolian transport of particles may cause serious damage in transportation, communications and severe environmental problems, such as the degradation of air quality due to dispersion of pollutants from stockpiles. The wind exposure will lead to the particles movement through several mechanisms, such as, suspension, creeping, saltation, and saltation bombardment. Consequently, the free surface will change over time due to entrainment and deposition phenomena. The main objective of this study is assessing the airflow characteristics over and around granular material complex three-dimensional piles when subjected to the wind erosion and its influence in the behavior of the free surface, as well as, in the sand emission rate. A literature review was made over the main subjects of interest to the present work, from the basics, such as granular material and aeolian transport mechanisms, to the key magnitudes involved in the wind erosion phenomena. Studies performed to calculate the dust emission from stockpiles are presented and reviewed along with the widely applied methodology from United States Environmental Protection Agency (USEPA). This methodology estimates the emission of particles from stockpiles only during specific erosion events, such as bursts, when in reality emissions occur in many other occasions. The present work offers the possibility of conducting the determination of emissions from stockpiles along time; this approach makes viable to follow the time-dependent evolution of the ...
Numerical and experimental study of granular piles when subjected to wind erosion
06.07.2018
101492260
Hochschulschrift
Elektronische Ressource
Englisch
Computational Fluid Dynamics (CFD) , OpenFOAM , Wind tunnel , Aeolian erosion , Emission rate , Shear Stress , Oblong piles , Triangular piles , Rectangular Duct , Irwin probes , Preston tube , Dinâmica de Fluidos Computacional , Túnel de vento , Erosão eólica , Taxa de emissão , Tensão de atrito , Pilhas Oblongas , Pilhas Triangulares , Conduta Retangular , sondas de Irwin , tubo de Preston , Engenharia Mecânica
DDC:
624
Experimental and Numerical Study on the Behavior of Energy Piles Subjected to Thermal Cycles
DOAJ | 2018
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