GFD オンラインセミナー (第 21 回)

日時: 2025 年 8 月 6 日 (水) 15:30--17:00

場所: zoom / 京大数理研本館 206 号室

講演者: Prof. Laura K. Currie
	(核融合科学研究所 客員研究員,
	 Department of Mathematical Sciences, Durham University, UK)

講演タイトル: Viscous dissipation and heat transport
	      in stratified convection: theory and simulations 

講演要旨:

Convection in astrophysical systems must be sustained against dissipative
losses. While viscous dissipation is often considered negligible, theoretical
arguments suggest that in strongly stratified convective fluids, the total
dissipative heating can exceed the luminosity transported by convection. We
investigate this possibility using a suite of numerical simulations of
non-rotating and rotating convection in a Cartesian layer under the anelastic
approximation. We show that the integrated viscous dissipation can indeed
surpass the imposed luminosity. Moreover, in highly supercritical regimes, the
total dissipation asymptotes to a value determined by the background thermal
stratification alone—becoming effectively independent of viscosity, thermal
diffusivity, or rotation rate. We also demonstrate that where the dissipation
occurs in the layer is important and has consequences for the convective flow
dynamics and heat transport. Finally, I will revisit an extension of Mixing
Length Theory (which in its non-rotating form is widely used to model stellar
and planetary convection) to include rotation and discuss how well it captures
the heat transport in our simulations of stratified convection.


開催方法: 対面 + zoom のハイブリッド形式

トピック: 第２１回GFDオンラインセミナー
時刻: 2025年8月6日 03:30 PM 大阪、札幌、東京
Zoom ミーティングに参加する
https://kyoto-u-edu.zoom.us/j/81772716309?pwd=azykVwTmR1KDsPGGYlFOs7atjBliCG.1

ミーティング ID: 817 7271 6309
パスコード: 742510