气候变化领域集成服务门户(CCPortal): Radiative heating achieves the ultimate regime of thermal convection

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DOI	10.1073/pnas.1806823115
	Radiative heating achieves the ultimate regime of thermal convection
	Lepot S.; Aumaître S.; Gallet B.
发表日期	2018
ISSN	0027-8424
起始页码	8937
结束页码	8941
卷号	115 期号:36
英文摘要	The absorption of light or radiation drives turbulent convection inside stars, supernovae, frozen lakes, and Earth’s mantle. In these contexts, the goal of laboratory and numerical studies is to determine the relation between the internal temperature gradients and the heat flux transported by the turbulent flow. This is the constitutive law of turbulent convection, to be input into large-scale models of such natural flows. However, in contrast with the radiative heating of natural flows, laboratory experiments have focused on convection driven by heating and cooling plates; the heat transport is then severely restricted by boundary layers near the plates, which prevents the realization of the mixing length scaling law used in evolution models of geophysical and astrophysical flows. There is therefore an important discrepancy between the scaling laws measured in laboratory experiments and those used, e.g., in stellar evolution models. Here we provide experimental and numerical evidence that radiatively driven convection spontaneously achieves the mixing length scaling regime, also known as the “ultimate” regime of thermal convection. This constitutes a clear observation of this regime of turbulent convection. Our study therefore bridges the gap between models of natural flows and laboratory experiments. It opens an experimental avenue for a priori determinations of the constitutive laws to be implemented into models of geophysical and astrophysical flows, as opposed to empirical fits of these constitutive laws to the scarce observational data. © 2018 National Academy of Sciences. All Rights Reserved.
英文关键词	Geophysical and astrophysical fluid dynamics; Thermal convection; Turbulence
语种	英语
scopus关键词	article; boundary layer; cooling; heat; heating; thermodynamics
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/158965
作者单位	Lepot, S., Service de Physique de l’Etat Condensé, Commissariat à l’Energie Atomique (CEA Saclay), CNRS UMR 3680, Université Paris-Saclay, Gif-sur-Yvette, 91191, France; Aumaître, S., Service de Physique de l’Etat Condensé, Commissariat à l’Energie Atomique (CEA Saclay), CNRS UMR 3680, Université Paris-Saclay, Gif-sur-Yvette, 91191, France, Laboratoire de Physique, Ecole Normale Supérieure de Lyon, UMR CNRS 5672, Lyon, 69007, France; Gallet, B., Service de Physique de l’Etat Condensé, Commissariat à l’Energie Atomique (CEA Saclay), CNRS UMR 3680, Université Paris-Saclay, Gif-sur-Yvette, 91191, France
推荐引用方式 GB/T 7714	Lepot S.,Aumaître S.,Gallet B.. Radiative heating achieves the ultimate regime of thermal convection[J],2018,115(36).
APA	Lepot S.,Aumaître S.,&Gallet B..(2018).Radiative heating achieves the ultimate regime of thermal convection.Proceedings of the National Academy of Sciences of the United States of America,115(36).
MLA	Lepot S.,et al."Radiative heating achieves the ultimate regime of thermal convection".Proceedings of the National Academy of Sciences of the United States of America 115.36(2018).