@misc{StarickMedinaMendezSchmidt, author = {Starick, Tommy and Medina M{\´e}ndez, Juan Ali and Schmidt, Heiko}, title = {One-Dimensional Turbulence simulations for reactive flows in open and closed systems}, series = {Technische Mechanik}, volume = {39}, journal = {Technische Mechanik}, number = {1}, doi = {10.24352/UB.OVGU-2019-015}, pages = {162 -- 174}, language = {en} } @inproceedings{MedinaMendezGlaweStaricketal., author = {Medina M{\´e}ndez, Juan Ali and Glawe, Christoph and Starick, Tommy and Sch{\"o}ps, Mark Simon and Schmidt, Heiko}, title = {IMEX-ODTLES: A multi-scale and stochastic approach for highly turbulent flows}, series = {90th Annual Meeting of the International Association of Applied Mathematics and Mechanics February 18-22, 2019 Vienna, Austria, Abstract book}, booktitle = {90th Annual Meeting of the International Association of Applied Mathematics and Mechanics February 18-22, 2019 Vienna, Austria, Abstract book}, publisher = {TU-Verlag}, address = {Wien}, isbn = {978-3-903024-84-7}, pages = {S. 540}, 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} } @misc{StarickMedinaMendezSchmidt, author = {Starick, Tommy and Medina M{\´e}ndez, Juan Ali and Schmidt, Heiko}, title = {Towards a dynamic model adaptive combustion closure using LEM, ODT, and HiPS}, series = {17th International Conference on Numerical Combustion, May 6-8, 2019, Aachen, Germany, Book of Abstracts}, journal = {17th International Conference on Numerical Combustion, May 6-8, 2019, Aachen, Germany, Book of Abstracts}, address = {Aachen}, pages = {143 -- 144}, abstract = {The computational cost of Direct Numerical Simulations (DNS) that resolve all scales rises with the cube of the Reynolds numberand is currently not feasible for real world applications. Large Eddy Simulations (LES) overcome this limitation by only resolving the large scale effects and completely model the small scaleeffects. This results in a strong dependence of the accuracy onthe chosen subgrid-scale model. The model adaptivity concept discussed in [Schmidt et al., ICDERS, 2007] dynamically uses different Linear Eddy Model (LEM) types [Kerstein, LEM, 1988] for stochastic closure to model the turbulent flame speed of apremixed flame within LES. In the talk, we will first summarize the progress of our group on One Dimensional Turbulence (ODT) [Kerstein, ODT, 1999] and Hierarchical Parcel Swapping (HiPS) [Kerstein, HiPS, 2013] based on reactive stand-alone simulations, [Jozefik et al., Combust. Flame, 2015] [Jozefik et al., Combust. Flame, 2016] [Medina et al., Combust. Flame, 2018]. Second,we will sketch a possible combination of the model adaptivity concept [Schmidt et al., ICDERS, 2007] and recent efficient ODTLES implementations [Glawe et al., Z. Angew. Math. Mech.,2018] to dynamically use LEM, ODT and HIPS together inside ofLES solvers to simulate turbulent reactive flows.}, language = {en} } @misc{StarickMedinaMendezKleinetal., author = {Starick, Tommy and Medina M{\´e}ndez, Juan Ali and Klein, Marten and Jozefik, Zoltan and Schmidt, Heiko}, title = {Zur j{\"u}ngsten Entwicklung in der Modellierung von turbulenten Verbrennungsprozessen mittels ODT}, series = {29. Deutscher Flammentag, 17-18 September 2019, Bochum, DE}, journal = {29. Deutscher Flammentag, 17-18 September 2019, Bochum, DE}, pages = {10}, abstract = {Die vorliegende Arbeit befasst sich mit den j{\"u}ngsten Entwicklungen und Anwendungen des One-Dimensional Turbulence (ODT) Modells auf reaktive Str{\"o}mungen. Bei ODT handelt es sich um ein stochastisches und abbildungsbasiertes Turbulenzmodell zur Simulation von turbulenten Str{\"o}mungen. In ODT wird das eindimensionale Rechengebiet als gedachte Linie durch das dreidimensionale Str{\"o}mungsfeld verstanden, welches in Richtung des mittleren Gradienten einer Geschwindigkeit oder anderer skalarer Felder orientiert ist. Die Besonderheit von ODT liegt in der Modellierung der turbulenten Advektion durch stochastisch auftretende Wirbelereignisse. Die molekulare Diffusion und Reaktionskinetik entlang des ODT-Rechengebietes wird mittels sich zeitlich entwickelnder, deterministischer Erhaltungsgleichungen ber{\"u}cksichtigt und vollst{\"a}ndig aufgel{\"o}st. In dieser Arbeit werden vorl{\"a}ufige ODT-Simulationsergebnisse von reaktiven Str{\"o}mungen f{\"u}r jeweilsein offenes und ein geschlossenes System vorgestellt. Essentielle Vorarbeiten, die die Vermischungeines passiven Skalars in einer planaren Strahld{\"u}se untersuchen, werden ebenfalls gezeigt. Beim offenen System handelt es sich um eine Methan/Luft Freistrahl-Flamme in einer umgebenden Str{\"o}mung aus heißen Verbrennungsgasen. Die Simulationsergebnisse werden zu Vergleichszweckenden Messungen von Cabra et al. gegen{\"u}bergestellt. Beim geschlossenen System wird die Selbstz{\"u}ndung von mageren n-Heptan Gemischen bei niedrigen Temperaturen und komplexer Reaktionskinetik betrachtet. Hierbei werden die ODT-Ergebnisse mit den Resultaten aus einer Direkten Numerischen Simulation (DNS) verglichen. In den durchgef{\"u}hrten Studien konnte gezeigt werden, dass die mittels ODT erzeugten Statistiken eine beachtlich gute {\"U}bereinstimmung mit den Vergleichsdaten aufweisen. Im Hinblick auf die reduzierte Dimensionalit{\"a}t von ODT, die Qualit{\"a}tder erzielten Ergebnisse und die erforderliche Rechenleistung, stellt ODT ein attraktives Modell zurSimulation von turbulenten und reaktiven Str{\"o}mungen dar.}, language = {de} } @misc{StarickMedinaMendezKleinetal., author = {Starick, Tommy and Medina M{\´e}ndez, Juan Ali and Klein, Marten and Jozefik, Zoltan and Schmidt, Heiko}, title = {Zur j{\"u}ngsten Entwicklung in der Modellierung von turbulenten Verbrennungsprozessen mittels ODT}, pages = {1}, language = {de} } @misc{MedinaMendezGlaweStaricketal., author = {Medina M{\´e}ndez, Juan Ali and Glawe, Christoph and Starick, Tommy and Sch{\"o}ps, Mark Simon and Schmidt, Heiko}, title = {IMEX-ODTLES: A multi-scale and stochastic approach for highly turbulent flows}, series = {Proceedings in Applied Mathematics and Mechanics}, volume = {19}, journal = {Proceedings in Applied Mathematics and Mechanics}, number = {1}, issn = {1617-7061}, doi = {10.1002/pamm.201900433}, abstract = {The stochastic One-Dimensional Turbulence (ODT) model is used in combination with a Large Eddy Simulation (LES) approach in order to illustrate the potential of the fully coupled model (ODTLES) for highly turbulent flows. In this work, we use a new C++ implementation of the ODTLES code in order to analyze the computational performance in a classical incompressible turbulent channel flow problem. The parallelization potential of the model, as well as its physical and numerical consistency are evaluated and compared to Direct Numerical Simulations (DNSs). The numerical results show that the model is capable of reproducing a representative part of the DNS data at a cheaper computational cost. This advantage can be enhanced in the future by the implementation of a straightforward parallelization approach.}, language = {en} } @misc{MedinaMendezSchmidtRiebel, author = {Medina M{\´e}ndez, Juan Ali and Schmidt, Heiko and Riebel, Ulrich}, title = {Towards a One-Dimensional Turbulence Approach for Electrohydrodynamic Flows}, series = {11th International Symposium on Turbulence and Shear Flow Phenomena (TSFP11), Southampton, UK, July 30 to August 2, 2019}, journal = {11th International Symposium on Turbulence and Shear Flow Phenomena (TSFP11), Southampton, UK, July 30 to August 2, 2019}, pages = {6}, abstract = {The One-Dimensional Turbulence model is modified in this work for its application to a classical electrohydrodynamic (EHD) problem. Being the first study case, this work is focused on the influence of electrostatic fields and space charge on the velocity field inside a wire-plate Electrostatic Precipitator (ESP) with one-way-coupling dynamics. The study case is an attempt to replicate velocity profiles and Turbulent Kinetic Energy (TKE) budgets obtained in the Direct Numerical Simulation (DNS) carried out by Soldati and Banerjee (1998). Qualitative trends are confirmed in preliminary ODT results, thus showing the potential of the stochastic ODT modeling approach for other types of EHD flows.}, language = {en} } @misc{MedinaMendezSchmidtRiebel, author = {Medina M{\´e}ndez, Juan Ali and Schmidt, Heiko and Riebel, Ulrich}, title = {Towards a One-Dimensional Turbulence Approach for Electrohydrodynamic Flows}, language = {en} } @misc{MedinaMendezSchmidtRiebel, author = {Medina M{\´e}ndez, Juan Ali and Schmidt, Heiko and Riebel, Ulrich}, title = {Extension of the One-Dimensional Turbulence model towards electrohydrodynamic variable density flows}, series = {17th European Turbulence Conference (ETC2019), 3-6 September 2019, Torino,}, journal = {17th European Turbulence Conference (ETC2019), 3-6 September 2019, Torino,}, address = {Turin}, pages = {1}, language = {en} } @misc{MedinaMendezKleinSchmidt, author = {Medina M{\´e}ndez, Juan Ali and Klein, Marten and Schmidt, Heiko}, title = {One-Dimensional Turbulence investigation of variable density effects due to heat transfer in a low Mach number internal air flow}, series = {International Journal of Heat and Fluid Flow}, volume = {80}, journal = {International Journal of Heat and Fluid Flow}, issn = {0142-727X}, doi = {10.1016/j.ijheatfluidflow.2019.108481}, pages = {19}, abstract = {A novel spatial formulation of the One-Dimensional Turbulence (ODT) model is applied to a vertical pipe-flow with heat transfer, analogous to the Direct Numerical Simulation (DNS) performed by Bae et al. [Phys. Fluids 18, (075102) (2006)]. The framework presented here is an extension for radially confined domains of the cylindrical ODT spatial formulation for low Mach number flows with variable density. The variable density simulations for air (Prandtl number Pr = 0.71) are performed at an initial bulk Reynolds number Reb (DNS) = 6000 and Grashof number Gr (DNS) = 6.78*10^6. ODT results are presented for both the spatial formulation introduced in this work and the standard temporal formulation for cylindrical flows introduced by Lignell et al. [Theor. Comput. Fluid Dyn. 32, 4 (2018), pp. 495-520]. Streamwise bulk profiles and radial profiles at specific streamwise positions for the temporal and spatial formulations are in good agreement with the DNS results from Bae et al. For the present application, the spatial formulation yields physically better results in comparison to the temporal formulation. Overall, the findings in the original work of Bae et al. were corroborated with ODT. Although the framework proposed in this work is not a compressible framework and has some clear limitations regarding conservation properties, we suggest its use for future studies in the low Mach number variable density regime.}, language = {en} } @misc{MedinaMendezSchmidtLignell, author = {Medina M{\´e}ndez, Juan Ali and Schmidt, Heiko and Lignell, David O.}, title = {Application of the One-Dimensional Turbulence model to incompressible channel and pipe flow}, series = {Publications Turbulent Reacting Flow Research Dr. David Lignell, Brigham Young University}, journal = {Publications Turbulent Reacting Flow Research Dr. David Lignell, Brigham Young University}, pages = {24}, language = {en} } @misc{MedinaMendezSchmidtRiebel, author = {Medina M{\´e}ndez, Juan Ali and Schmidt, Heiko and Riebel, Ulrich}, title = {Towards a One-Dimensional Turbulence Approach for Electrohydrodynamic Flows}, series = {11th International Symposium on Turbulence and Shear Flow Phenomena (TSFP11), Southampton, UK, July 30 to August 2, 2019}, journal = {11th International Symposium on Turbulence and Shear Flow Phenomena (TSFP11), Southampton, UK, July 30 to August 2, 2019}, pages = {1}, language = {en} }