TY - JOUR
T1 - Interplay between advective, diffusive and active barriers in (rotating) Rayleigh–Bénard flow
AU - Aksamit, Nikolas O.
AU - Hartmann, Robert
AU - Lohse, Detlef
AU - Haller, George
N1 - Funding Information:
N.O.A. and G.H. acknowledge financial support from Priority Program SPP 1881 (Turbulent Superstructures) of the German National Science Foundation (DFG). N.O.A. acknowledges financial support from the Swiss National Science Foundation (SNSF) Postdoc Mobility Fellowship Project P400P2 199190. R.H. and D.L. acknowledge funding by the ERC Starting Grant UltimateRB (no. 804283/ERC-2018-STG) and ERC Advanced Grant DDD (ERC-2016-ADG).
Funding Information:
We acknowledge PRACE for awarding us access to MareNostrum 4 based in Spain at the Barcelona Computing Center (BSC) under project 2020235589. This work was partially carried out on the Dutch national e-infrastructure with the support of SURF Cooperative. The authors would also like to thank R. Verzicco and R.J.A.M. Stevens for engaging discussions on this topic.
Publisher Copyright:
© 2023 The Author(s).
PY - 2023/8/25
Y1 - 2023/8/25
N2 - Our understanding of the material organization of complex fluid flows has benefited recently from mathematical developments in the theory of objective coherent structures. These methods have provided a wealth of approaches that identify transport barriers in three-dimensional (3-D) turbulent flows. Specifically, theoretical advances have been incorporated into numerical algorithms that extract the most influential advective, diffusive and active barriers to transport from data sets in a frame-indifferent fashion. To date, however, there has been very limited investigation into these objectively defined transport barriers in 3-D unsteady flows with complicated spatiotemporal dynamics. Similarly, no systematic comparison of advective, diffusive and active barriers has been carried out in a 3-D flow with both thermally driven and mechanically modified structures. In our study, we utilize simulations of turbulent rotating Rayleigh–Bénard convection to uncover the interplay between advective transport barriers (Lagrangian coherent structures), material barriers to diffusive heat transport, and objective Eulerian barriers to momentum transport. For a range of (inverse) Rossby numbers, we identify each type of barrier and find intriguing relationships between momentum and heat transport that can be related to changes in the relative influence of mechanical and thermal forces. Further connections between bulk behaviours and structure-specific behaviours are also developed.
AB - Our understanding of the material organization of complex fluid flows has benefited recently from mathematical developments in the theory of objective coherent structures. These methods have provided a wealth of approaches that identify transport barriers in three-dimensional (3-D) turbulent flows. Specifically, theoretical advances have been incorporated into numerical algorithms that extract the most influential advective, diffusive and active barriers to transport from data sets in a frame-indifferent fashion. To date, however, there has been very limited investigation into these objectively defined transport barriers in 3-D unsteady flows with complicated spatiotemporal dynamics. Similarly, no systematic comparison of advective, diffusive and active barriers has been carried out in a 3-D flow with both thermally driven and mechanically modified structures. In our study, we utilize simulations of turbulent rotating Rayleigh–Bénard convection to uncover the interplay between advective transport barriers (Lagrangian coherent structures), material barriers to diffusive heat transport, and objective Eulerian barriers to momentum transport. For a range of (inverse) Rossby numbers, we identify each type of barrier and find intriguing relationships between momentum and heat transport that can be related to changes in the relative influence of mechanical and thermal forces. Further connections between bulk behaviours and structure-specific behaviours are also developed.
U2 - 10.1017/jfm.2023.563
DO - 10.1017/jfm.2023.563
M3 - Article
SN - 0022-1120
VL - 969
JO - Journal of fluid mechanics
JF - Journal of fluid mechanics
M1 - A27
ER -