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عنوان فارسی مقاله:
شبیه سازی عددی 3D روند تکاملی بادی تپه های شنی هلالی شکل کوچک
عنوان انگلیسی مقاله:
3D numerical simulation of the evolutionary process of aeolian downsized crescent-shaped dunes
سال انتشار : 2016
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مقدمه انگلیسی مقاله:
1. Introduction
Barchans are crescent-shaped dunes formed under the actions of wind field with a single wind direction. Barchans attract widespread attention because of their unique structure, selforganising evolution and high-rate migration. Field observations indicate that migrating dunes of natural scale may take several months to several years to achieve total migration (Bagnold, 1941; Pye and Tsoar, 2009; Ewing et al., 2015). Downsized dunes are typically used to simulate dunes in real scale because of the finite size of a wind tunnel (Andreotti et al., 2002; Dauchot et al., 2002; Faria et al., 2011; Zhang et al., 2014). Dynamic numerical simulation is an alternative technique to field research to study dunes. This approach not only reveals the evolution of dunes at any scale but also enables the exploration of the influence of various factors on dune evolution under controllable conditions. Numerical simulation of the evolutionary process of dunes consumes reduced amount of time and is characterised by continuity, repeatability and independence from environmental factors. Therefore, numerical simulation provides great benefits as a supplement to wind tunnel simulation. Simulation of the evolution and migration of dunes in a wind field poses greater challenges compared with simulation of nearsurface wind-sand flow. The formation and migration of dunes are caused by interaction among three processes, namely, surface air flow movement, macroscopic surface changes and microscopic sand grain transport. The evolution and migration of dunes on the macroscopic scale are related to the characteristics of air and sand flow, as well as the erosion and deposition patterns of sand phase. Generally, dunes can be more comprehensively described by macroscopic parameters than by microscopic parameters. Studies have shown that the mesoscale aspects of sand flux are of greater significance than the characteristics of grains that constitute dunes in morphological research (Sauermann et al., 2001a; Hersen et al., 2002). Sauermann et al. (2001b) conducted field measurements of dunes and found that the content of grains that constitute an independent barchan reached an order of magnitude of about 1015 (one thousand trillions). Therefore, simulating discrete grain size is difficult in the field of dune morphology. Numerous studies adopt the macroscopic scale to investigate the migration dynamics of dunes (Kok et al., 2012). Thus far, the proposed representative models include the continuous minimal model (Sauermann et al., 2001a,b; Kroy et al., 2002) and the discrete cellular automaton (CA) model (Werner, 1995). These two models have been constantly improved in subsequent studieson models for dunes. The application of the continuous minimal model has been extended from 2D dunes to 3D dunes (Schwammle and Herrmann, 2005; Parteli et al., 2014a), from a single dune to multiple dunes (Duran et al., 2010) and even to dunes on Mars (Parteli et al., 2007). Katsuki et al. (2005) drew on the principle of the CA model and proposed a calculation model that considered saltation and avalanche. The dynamic process of migration and collision of aqueous barchans was reproduced by simulation. Narteau et al. (2009) proposed a lattice-gas cellular automaton model based on the CA model. Changes in the 3D morphology of dunes and shear stress on the dune surface in real space were simulated. The correlation between discrete and continuous simulation methods was established. This model was also used to study sand transport capacity and saturation mechanism (Gao et al., 2014). Bishop et al. (2002) improved the CA model through physical excitation. Discrete lattice dynamics method realistically simulated the formation and evolution of dune fields. As an available model with insights obtained from the minimal model (Parteli et al., 2014a), the CA model has been used to deepen our understanding of aeolian landscape development (Baas, 2013). Lima et al. (2002) proposed a model for the development of dune fields; in this model, barchans were treated as ‘‘interacting particles.” The same kind of spatial correlations between dunes could be reproduced similar to that in real fields by using the rule of inter-dune sand flux for interaction among dunes. This type of model was subsequently extended to simulate the evolution of a transverse dune field. Field dunes with almost the same height and velocity were reproduced, and this process was not influenced by the initial con- figuration of the field and coalescence between dunes (Parteli and Herrmann, 2003). Zheng et al. (2009) proposed a comprehensive scale-coupled model of dune fields. The scale difference between grains and dunes was resolved by drawing on the concept of sand body element. The trans-scale simulation of the evolution of sand dune field was then established.
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کلمات کلیدی:
Flow effects on the morphology and dynamics of aeolian and ... onlinelibrary.wiley.com/doi/10.1029/2004JF000185/full by P Hersen - 2005 - Cited by 52 - Related articles Nov 16, 2005 - This comes from erosion and deposition processes: the wind carries .... Formation and evolution of a subaqueous barchan dune created by the ... Flow effects on the morphology and dynamics of aeolian and ... onlinelibrary.wiley.com/doi/10.1029/2004JF000185/abstract by P Hersen - 2005 - Cited by 52 - Related articles Nov 16, 2005 - Abstract. [1] Barchans are aeolian sand dunes that form where unidirectional winds blow on firm ground with limited sand supply. Although they ... Modelling desert dune fields based on discrete dynamics - Hindawi https://www.hindawi.com/journals/ddns/2002/275454/citations/ ... ripple marks in a wave flume,” Earth Surface Processes and Landforms, vol. .... evolutionary process of aeolian downsized crescent-shaped dunes,” Aeolian ... Evolution of downsized crescent-shaped dune in wind tunnel ... link.springer.com/10.1007/s11433-013-5261-8 by Y Zhang - 2014 - Cited by 2 - Related articles Sep 6, 2013 - Abstract. The migration of a downsized crescent-shaped dune was investigated in a wind tunnel experiment. Quantified upwind influx and ... Article metrics for: Sand dune patterns on Titan controlled by long-term ... www.nature.com › Home › archive › issue › Letter › Article › Article metrics Dec 8, 2014 - Citations for this article. 3D numerical simulation of the evolutionary process of aeolian downsized crescent-shaped dunes. Xiaosi Zhou,; Yang ... Evolution of downsized crescent-shaped dune in wind tunnel experiment phys.scichina.com:8083/sciGe/fileup/PDF/11433_OF_13_5261.pdf Citation: Zhang Y, Wang Y, Jia P. Evolution of downsized crescent-shaped dune in wind tunnel experiment. ... aspects of aeolian sand physics and the complex result of ... downwind in a repeated process that varies between erosion. Subaqueous barchan dunes in turbulent shear flow. Part 1. Dune motion https://www.cambridge.org/...in.../4ECDE3F1E63CE454A33ECEB927697106 by EM FRANKLIN - 2011 - Cited by 40 - Related articles Mar 30, 2011 - B. Andreotti , P. Claudin & O. Pouliquen 2010 Measurements of the aeolian sand transport saturation length. Geomorphology 123, 343–348.
