图书馆订阅: Guest
Begell Digital Portal Begell 数字图书馆 电子图书 期刊 参考文献及会议录 研究收集
多孔介质专题评论
ESCI SJR: 0.259 SNIP: 0.466 CiteScore™: 0.83

ISSN 打印: 2151-4798
ISSN 在线: 2151-562X

多孔介质专题评论

DOI: 10.1615/SpecialTopicsRevPorousMedia.2017019609
pages 91-108

NUMERICAL SIMULATION OF CONVECTIVE CURRENTS IN AQUATIC CANOPIES USING A MACROSCOPIC MODEL

Maria Tsakiri
Hydraulics Laboratory, Department of Civil Engineering, Aristotle University of Thessaloniki, Thessaloniki, 54124, Greece
Panayotis Prinos
Hydraulics Laboratory, Department of Civil Engineering, Aristotle University of Thessaloniki, Thessaloniki, 54124, Greece

ABSTRACT

In the present study, convective currents between open water and aquatic canopies are numerically investigated using a macroscopic model. The convective currents are produced due to differential radiation absorption between the two regions. The unsteady two-dimensional volume-averaged Navier-Stokes equations are used and the vegetation effects are taken into account through additional resistance terms using a porous media approach based on porous medium permeability. The model can be used even for vegetation with a complicated structure (stems, foliage) in which the vegetation permeability k can be easily determined. Seven cases with vegetation porosity φ from 0.75 to 0.97 and one case without vegetation are examined to investigate the vegetation effects on the motion of the convective currents. Thus, cases with low vegetation porosity (φ < 0.85) are also investigated, in which there is no sufficient information. A microscopic model, which uses the unsteady three-dimensional Navier-Stokes equations to simulate the flow characteristics around individual vegetation elements, is also used for comparison purposes. The energy equation is also solved in both models, in which the absorption of radiation is taken into account through an additional term. The Boussinesq approximation is applied to take into account the density difference due to the temperature difference. The numerical results for the current velocity and water temperature obtained from both models are presented and compared against available experimental data. Empirical relationships between the current velocity and vegetation porosity are also derived, which can be used for further investigation.


Articles with similar content:

Application of a Simple Space-Time Averaged Porous Media Model to Flow in Densely Vegetated Channels
Journal of Porous Media, Vol.7, 2004, issue 3
Marc R. Hoffmann
A Continuum Approach to Multiphase Flows in Porous Media
Journal of Porous Media, Vol.2, 1999, issue 3
Shijie Liu
THREE-DIMENSIONAL NUMERICAL SIMULATION OF A THREE-LAYERED RADIANT POROUS HEAT EXCHANGER WITH VARIABLE GAS PROPERTIES
Journal of Porous Media, Vol.16, 2013, issue 11
E. Jahanshahi Javaran, Mohammad Sajedi, S. A. Gandjalikhan Nassab
Modeling of Langmuir circulation : triple decomposition of the Craik - Leibovitch model
ICHMT DIGITAL LIBRARY ONLINE, Vol.0, 2012, issue
Chester E. Grosch, Thomas B. Gatski, Guillaume Martinat
NUMERICAL SIMULATION OF HYDROTHERMAL PROCESSES IN LAKE Drûkðiai. 5. THE TWO-PHASE MODEL
ENERGETIKA, Vol.1, 2004, issue 4
Antanas Markevieius, Petras Vaitiekunas, Vladislavas Katinas, Jelena Shaimardanova