@inproceedings{KleinSchmidt, author = {Klein, Marten and Schmidt, Heiko}, title = {Towards numerical simulation of the ultimate state of convection using one-dimensional turbulence modeling}, series = {International Conference on Rayleigh B{\´e}nard Convection, May 14-18, Enschede, The Netherlands, abstracts}, booktitle = {International Conference on Rayleigh B{\´e}nard Convection, May 14-18, Enschede, The Netherlands, abstracts}, pages = {1}, language = {en} } @inproceedings{KleinSchmidt, author = {Klein, Marten and Schmidt, Heiko}, title = {Stochastic Modeling of Passive Scalar Transport in Turbulent Channel Flows at High Schmidt Numbers}, series = {10th International Symposium on Turbulence and Shear Flow Phenomena (TSFP10), Chicago, USA, July, 2017}, booktitle = {10th International Symposium on Turbulence and Shear Flow Phenomena (TSFP10), Chicago, USA, July, 2017}, pages = {7}, language = {en} } @inproceedings{KleinSchmidt, author = {Klein, Marten and Schmidt, Heiko}, title = {Investigating the Reynolds number dependency of the scalar transfer to a wall using a stochastic turbulence model}, series = {89th Annual Meeting of the International Association of Applied Mathematics and Mechanics March 19-23, 2018 Munich, Germany, Book of abstracts}, booktitle = {89th Annual Meeting of the International Association of Applied Mathematics and Mechanics March 19-23, 2018 Munich, Germany, Book of abstracts}, publisher = {GAMM}, pages = {S. 287}, language = {en} } @inproceedings{KleinSchmidt, author = {Klein, Marten and Schmidt, Heiko}, title = {On Turbulent Scalar Transport at Very High Schmidt Numbers Using a Stochastic Modeling Appro}, series = {88th Annual Meeting of the International Association of Applied Mathematics and Mechanics March 6-10, 2017 Weimar, Germany, Book of abstacts}, booktitle = {88th Annual Meeting of the International Association of Applied Mathematics and Mechanics March 6-10, 2017 Weimar, Germany, Book of abstacts}, publisher = {GAMM}, pages = {357 -- 358}, language = {en} } @misc{LignellLansingerMedinaMendezetal., author = {Lignell, David O. and Lansinger, Victoria B. and Medina M{\´e}ndez, Juan Ali and Klein, Marten and Kerstein, Alan R. and Schmidt, Heiko and Fistler, Marco and Oevermann, Michael}, title = {One-dimensional turbulence modeling for cylindrical and spherical flows: model formulation and application}, series = {Theoretical and Computational Fluid Dynamics}, volume = {32}, journal = {Theoretical and Computational Fluid Dynamics}, number = {4}, issn = {0935-4964}, doi = {10.1007/s00162-018-0465-1}, pages = {495 -- 520}, abstract = {The one-dimensional turbulence (ODT) model resolves a full range of time and length scales and is computationally efficient. ODT has been applied to a wide range of complex multi-scale flows, such as turbulent combustion. Previous ODT comparisons to experimental data have focused mainly on planar flows. Applications to cylindrical flows, such as round jets, have been based on rough analogies, e.g., by exploiting the fortuitous consistency of the similarity scalings of temporally developing planar jets and spatially developing round jets. To obtain a more systematic treatment, a new formulation of the ODT model in cylindrical and spherical coordinates is presented here. The model is written in terms of a geometric factor so that planar, cylindrical, and spherical configurations are represented in the same way. Temporal and spatial versions of the model are presented. A Lagrangian finite-volume implementation is used with a dynamically adaptive mesh. The adaptive mesh facilitates the implementation of cylindrical and spherical versions of the triplet map, which is used to model turbulent advection (eddy events) in the one-dimensional flow coordinate. In cylindrical and spherical coordinates, geometric stretching of the three triplet map images occurs due to the radial dependence of volume, with the stretching being strongest near the centerline. Two triplet map variants, TMA and TMB, are presented. In TMA, the three map images have the same volume, but different radial segment lengths. In TMB, the three map images have the same radial segment lengths, but different segment volumes. Cylindrical results are presented for temporal pipe flow, a spatial nonreacting jet, and a spatial nonreacting jet flame. These results compare very well to direct numerical simulation for the pipe flow, and to experimental data for the jets. The nonreacting jet treatment overpredicts velocity fluctuations near the centerline, due to the geometric stretching of the triplet maps and its effect on the eddy event rate distribution. TMB performs better than TMA. A hybrid planar-TMB (PTMB) approach is also presented, which further improves the results. TMA, TMB, and PTMB are nearly identical in the pipe flow where the key dynamics occur near the wall away from the centerline. The jet flame illustrates effects of variable density and viscosity, including dilatational effects.}, language = {en} } @misc{KleinSchmidt, author = {Klein, Marten and Schmidt, Heiko}, title = {Investigating the Reynolds number dependency of the scalar transfer to a wall using a stochastic turbulence model}, series = {Proceedings in applied mathematics and mechanics : PAMM}, volume = {18}, journal = {Proceedings in applied mathematics and mechanics : PAMM}, number = {1}, issn = {1617-7061}, doi = {10.1002/pamm.201800238}, pages = {2}, language = {en} } @misc{KleinSchmidt, author = {Klein, Marten and Schmidt, Heiko}, title = {Stochastic Modeling of Turbulent Scalar Transport at Very High Schmidt Numbers}, series = {Proceedings in applied mathematics and mechanics : PAMM}, volume = {17}, journal = {Proceedings in applied mathematics and mechanics : PAMM}, number = {1}, issn = {1617-7061}, doi = {10.1002/pamm.201710289}, pages = {639 -- 640}, language = {en} } @misc{VinczeFenyvesiKleinetal., author = {Vincze, Miklos and Fenyvesi, Nora and Klein, Marten and Sommeria, Joel and Viboud, Samuel and Ashkenazy, Yossi}, title = {Evidence for wind-induced Ekman layer resonance based on rotating tank experiments}, series = {EPL : a letters journal exploring the frontiers of physics}, volume = {125}, journal = {EPL : a letters journal exploring the frontiers of physics}, number = {4}, issn = {1286-4854}, doi = {10.1209/0295-5075/125/44001}, pages = {1 -- 7}, abstract = {The temporal variability of wind stress acting on the ocean surface may have a significant impact on the energy transfer between the surface ocean and the abyssal ocean. In particular, the surface ocean layer is expected to deepen when the wind's frequency matches the inertial (Coriolis) frequency, through "Ekman layer resonance". Here, we report on laboratory experiments conducted in the large circular rotating tank of the LEGI Coriolis platform (13 m in diameter and 0.5 m in depth) to investigate the effect of oscillating horizontal shear imposed at the water surface. The analysis of the flow structure by means of particle image velocimetry (PIV) reveals a resonant thickening of the top Ekman layer and a marked increase in the kinetic energy of the flow occurs when the forcing frequency coincides with the Coriolis frequency of the rotating tank. The findings are in agreement with the theoretical expectations and constitute evidence for the existence of the Ekman layer resonance (or near inertial resonance) phenomenon in an ocean-like configuration.}, language = {en} } @misc{KleinLignellSchmidt, author = {Klein, Marten and Lignell, David O. and Schmidt, Heiko}, title = {Map-Based Modeling of Turbulent Convection: Application of the One-Dimensional Turbulence Model to Planar and Spherical Geometries}, pages = {1}, language = {en} } @misc{KleinSchmidt, author = {Klein, Marten and Schmidt, Heiko}, title = {Map-based Modeling of Turbulent Boundary Layers Subject to Rotation and Stratification}, pages = {1}, language = {en} } @misc{KleinZenkerSchmidt, author = {Klein, Marten and Zenker, Christian and Schmidt, Heiko}, title = {Small-scale resolving simulations of the turbulent mixing in confined planar jets using one-dimensional turbulence}, series = {Chemical Engineering Science}, volume = {204}, journal = {Chemical Engineering Science}, issn = {0009-2509}, pages = {186 -- 202}, language = {en} } @misc{GhasemiKleinWilletal., author = {Ghasemi, Abouzar and Klein, Marten and Will, Andreas and Harlander, Uwe}, title = {Mean flow generation by an intermittently unstable boundary layer over a sloping wall}, series = {Journal of Fluid Mechanics}, journal = {Journal of Fluid Mechanics}, number = {vol. 853}, issn = {1750-6859}, doi = {10.1017/jfm.2018.552}, pages = {111 -- 149}, language = {en} } @misc{KleinSchmidt, author = {Klein, Marten and Schmidt, Heiko}, title = {Investigating the skin friction drag across electrolytes and electrical fields using one-dimensional turbulence modeling}, series = {European Drag Reduction and Flow Control Meeting, EDRFCM 2019, March 26-29 2019, Bad Herrenalb, Germany}, journal = {European Drag Reduction and Flow Control Meeting, EDRFCM 2019, March 26-29 2019, Bad Herrenalb, Germany}, pages = {1 -- 2}, language = {en} } @misc{KleinLignellSchmidt, author = {Klein, Marten and Lignell, David O. and Schmidt, Heiko}, title = {Stochastic modeling of temperature and velocity statistics in spherical-shell convection}, series = {Geophysical Research Abstracts, Vol. 21, EGU2019-2220}, journal = {Geophysical Research Abstracts, Vol. 21, EGU2019-2220}, pages = {1}, language = {en} } @misc{SchmidtKlein, author = {Schmidt, Heiko and Klein, Marten}, title = {Simulating neutrally and stably stratified turbulent Ekman flows with a stochastic turbulence model}, series = {Proc. of the 17th European Turbulence Conference (ETC17), 3-6 September 2019, Torino, Italy}, journal = {Proc. of the 17th European Turbulence Conference (ETC17), 3-6 September 2019, Torino, Italy}, pages = {1}, language = {en} } @misc{SommeriaVinczeFenyvesietal., author = {Sommeria, Joel and Vincze, Miklos and Fenyvesi, Nora and Klein, Marten and Viboud, Samuel and Ashkenazy, Yosef}, title = {Ekman layer resonance in an ocean-analog rotating tank experiment}, series = {17th European Turbulence Conference, Turin, 3 Sep 2019 - 6 Sep 2020}, journal = {17th European Turbulence Conference, Turin, 3 Sep 2019 - 6 Sep 2020}, language = {en} } @misc{KleinSchmidt, author = {Klein, Marten and Schmidt, Heiko}, title = {Investigating Rayleigh-B{\´e}nard convection at low Prandtl numbers using one-dimensional turbulence modeling}, series = {Proc. of the 11th International Symposium on Turbulence and Shear Flow Phenomena (TSFP11), Southampton, UK, July 30 to August 2, 2019}, journal = {Proc. of the 11th International Symposium on Turbulence and Shear Flow Phenomena (TSFP11), Southampton, UK, July 30 to August 2, 2019}, pages = {6}, language = {en} } @misc{KleinSchmidt, author = {Klein, Marten and Schmidt, Heiko}, title = {Investigating thermal convection at low Prandtl numbers using one-dimensional turbulence}, pages = {1}, language = {en} } @misc{KleinSchmidt, author = {Klein, Marten and Schmidt, Heiko}, title = {The transition to the ultimate regime of thermal convection from a stochastic one-dimensional turbulence perspective}, series = {arXiv}, journal = {arXiv}, pages = {1 -- 11}, language = {en} } @misc{RakhiKleinMedinaMendezetal., author = {Rakhi, Rakhi and Klein, Marten and Medina M{\´e}ndez, Juan Ali and Schmidt, Heiko}, title = {One-dimensional turbulence modelling of incompressible temporally developing turbulent boundary layers with comparison to DNS}, series = {Journal of Turbulence}, volume = {20}, journal = {Journal of Turbulence}, number = {8}, issn = {1468-5248}, doi = {10.1080/14685248.2019.1674859}, pages = {506 -- 543}, abstract = {The incompressible temporally developing turbulent boundary layer (TBL) is analysed using the map-based stochastic one-dimensional turbulence (ODT) model. The TBL is a canonical flow problem, which is, in the present study, formed by a planar moving wall and a free stream at rest. An understanding of this idealised flow is of fundamental relevance for the numerical analysis of turbulent boundary-layer-type flows. In the present ODT simulations, the flow variables are resolved on all scales along a wall-normal, one-dimensional domain. These variables are evolved by a deterministic and a stochastic process. The latter models the effect of turbulent advection and pressure fluctuations, whereas the former represents molecular diffusion. The model is appropriate for high Reynolds numbers for which the turbulence field exhibits a broad range of scales and is notionally featureless. We show that ODT is able to capture salient features of the TBL by comparing the various statistics with available reference direct numerical simulation (DNS) results for different bulk Reynolds numbers in the range 250 ≤ Reb ≤ 2000 using fixed model parameters. The influence of the model parameters is analysed for Reb = 1000 and optimal parameter values are provided. The results discussed in this paper suggest that ODT is an economical and reasonably accurate approach for the simulation of transient turbulent boundary-layer-type flows.}, language = {en} }