The drag coefficient and settling velocity of natural sediment particles
| Autor: | Umut Türker, Amin Riazi |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Fluid Flow and Transfer Processes
050101 languages & linguistics Numerical Analysis Drag coefficient 05 social sciences Computational Mechanics Reynolds number 02 engineering and technology Mechanics Function (mathematics) Gravitational acceleration Nominal size Computational Mathematics symbols.namesake Settling Modeling and Simulation 0202 electrical engineering electronic engineering information engineering symbols Range (statistics) Particle 020201 artificial intelligence & image processing 0501 psychology and cognitive sciences Civil and Structural Engineering Mathematics |
| Zdroj: | Computational Particle Mechanics. 6:427-437 |
| ISSN: | 2196-4386 2196-4378 |
| Popis: | This article reports a study in which drag coefficient is defined more comprehensively. The coefficient is defined as a function of particle nominal diameter, gravitational acceleration, the ambient fluid kinematic viscosity, and the particle shape. This new definition is different from the conventional definitions proposed in the literature based on direct equations as a function of particle Reynolds number. The conventional definitions appear to be a simplification of drag coefficient and thus decreasing the accuracy of the estimations. Instead, the proposed equation in this article indicates that on average the drag coefficient estimation can be improved at least 3.77% compared to the proposed drag coefficient widely used in the literature. The improved drag coefficient was used to derive a more accurate settling velocity equation in which the effect of particle shape is directly incorporated in the settling velocity equation. Both equations were validated using well known datasets and accurate experiments from the literature as well as new experiments conducted for this purpose in the current research. The experiments cover a wide range of particle shape and a variety of specific gravity. The outcomes of the current study contribute to the use of settling velocity in river hydraulic applications proposing a simpler but more accurate procedure. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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