TY - JOUR

T1 - Lagrangian Coherent Sets as transport barriers in convection

AU - Schumacher, Jörg

AU - Vieweg, Philipp P.

AU - Schneide, Christiane

AU - Padberg-Gehle, Kathrin

N1 - Conference code: 73

PY - 2020

Y1 - 2020

N2 - Lagrangian Coherent Sets as transport barriers in convection1JOERG SCHUMACHER, PHILIPP VIEWEG, TU Ilmenau, CHRISTIANESCHNEIDE, KATHRIN PADBERG-GEHLE, Leuphana University Lueneburg —The analysis of the turbulent heat transfer in thermal convection flow is mostlydone in the Eulerian frame of reference. Here, we use an ensemble of more thanhalf a million individual Lagrangian tracer trajectories, which are advected togetherwith the evolving turbulent flow, to identify subsets that contribute least to theheat transfer. These trajectories probe Lagrangian Coherent Sets sets that remainspatially connected for a finite time and evolve in time. The analysis is based onthree-dimensional direct numerical simulations at three different Prandtl numbers.Our Lagrangian analysis results provide a complementary view on the transport andare found to be consistent with the standard Eulerian results.1 The work is supported by the Priority Programme DFG-SPP 1881 of the DeutscheForschungsgemeinschaft.

AB - Lagrangian Coherent Sets as transport barriers in convection1JOERG SCHUMACHER, PHILIPP VIEWEG, TU Ilmenau, CHRISTIANESCHNEIDE, KATHRIN PADBERG-GEHLE, Leuphana University Lueneburg —The analysis of the turbulent heat transfer in thermal convection flow is mostlydone in the Eulerian frame of reference. Here, we use an ensemble of more thanhalf a million individual Lagrangian tracer trajectories, which are advected togetherwith the evolving turbulent flow, to identify subsets that contribute least to theheat transfer. These trajectories probe Lagrangian Coherent Sets sets that remainspatially connected for a finite time and evolve in time. The analysis is based onthree-dimensional direct numerical simulations at three different Prandtl numbers.Our Lagrangian analysis results provide a complementary view on the transport andare found to be consistent with the standard Eulerian results.1 The work is supported by the Priority Programme DFG-SPP 1881 of the DeutscheForschungsgemeinschaft.

KW - Mathematics

UR - http://flux.aps.org/meetings/YR20/DFD20/all_DFD20.pdf

M3 - Conference abstract in journal

VL - 65

JO - Bulletin of the American Physical Society

JF - Bulletin of the American Physical Society

SN - 0003-0503

IS - 13

M1 - F16.00009

T2 - 73rd Annual Meeting of the APS Division of Fluid Dynamics - 2021

Y2 - 22 November 2020 through 24 November 2020

ER -