气候变化领域集成服务门户(CCPortal): Evolution and Features of Dust Devil-Like Vortices in Turbulent Rayleigh-Bénard Convection—A Numerical Study Using Direct Numerical Simulation

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DOI	10.1029/2020JD034334
	Evolution and Features of Dust Devil-Like Vortices in Turbulent Rayleigh-Bénard Convection—A Numerical Study Using Direct Numerical Simulation
	Giersch S.; Raasch S.
发表日期	2021
ISSN	2169897X
卷号	126 期号:7
英文摘要	Dust devils are convective vortices with a vertical axis of rotation that are made visible by entrained soil particles. These soil particles contribute to the atmospheric aerosol input, influencing the Earth radiation budget. Quantifying this contribution requires reliable information about the statistics of dust devils, their formation process, and how they are maintained. In the past, this information was mainly derived from field experiments and large-eddy simulations (LESs). Field experiments suffer from the erratic occurrence of dust devils and the limited area that can be monitored reliably. In LESs, dust devils cannot be resolved completely, especially close to the ground. Additionally, they are affected by numerical features of surface boundary conditions, as well as subgrid-scale models in an unknown way. To mitigate these limitations, we employ direct numerical simulations (DNSs) to improve our understanding of dust devils. We comprehensively investigate the statistics and structure of dust devils for Rayleigh numbers up to 1011 using DNS of Rayleigh-Bénard convection between two plates for the first time. We find that dust devil-like structures occur in DNS with Rayleigh numbers much lower than in the atmosphere (≥107). These results support previous DNS studies in which vortices with vertical axes were observed but not further investigated. The dust devil statistics strongly depend on the Rayleigh number and velocity boundary conditions, but depend little on the aspect ratio of the model domain. Simulated dust devils show very similar properties to convective vortices analyzed in LESs of the atmospheric boundary layer. © 2021. The Authors.
英文关键词	direct numerical simulation; dust devils; Rayleigh-Bénard convection
语种	英语
来源期刊	Journal of Geophysical Research: Atmospheres
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/185335
作者单位	Institute of Meteorology and Climatology, Leibniz University Hannover, Hannover, Germany
推荐引用方式 GB/T 7714	Giersch S.,Raasch S.. Evolution and Features of Dust Devil-Like Vortices in Turbulent Rayleigh-Bénard Convection—A Numerical Study Using Direct Numerical Simulation[J],2021,126(7).
APA	Giersch S.,&Raasch S..(2021).Evolution and Features of Dust Devil-Like Vortices in Turbulent Rayleigh-Bénard Convection—A Numerical Study Using Direct Numerical Simulation.Journal of Geophysical Research: Atmospheres,126(7).
MLA	Giersch S.,et al."Evolution and Features of Dust Devil-Like Vortices in Turbulent Rayleigh-Bénard Convection—A Numerical Study Using Direct Numerical Simulation".Journal of Geophysical Research: Atmospheres 126.7(2021).