@misc{MedinaMendezSchmidtMaussetal., author = {Medina M{\´e}ndez, Juan Ali and Schmidt, Heiko and Mauß, Fabian and Jozefik, Zoltan}, title = {Constant volume n-Heptane autoignition using One-Dimensional Turbulence}, series = {Combustion and Flame}, volume = {190}, journal = {Combustion and Flame}, issn = {0010-2180}, doi = {10.1016/j.combustflame.2017.12.015}, pages = {388 -- 401}, abstract = {Abstract Constant volume premixed lean n-Heptane/air autoignition at high pressure is investigated using the One-Dimensional Turbulence (ODT) model. The configuration consists of a 1D fixed volume domain with a prescribed velocity spectrum and temperature fluctuations superimposed on an initial uniformly elevated scalar field. The sensitivity of the heat release rate and pressure evolution to the initial temperature distribution is studied by imposing different initial temperature fields while holding the mean, RMS and integral length scale of the field constant. Three detailed chemical mechanisms are employed for the prediction of autoignition and heat release rate. To mitigate the high computational cost associated with the calculation of the chemical source terms in the stiff complex mechanisms, an approach based on the Strang-Splitting method is presented. Finally, a …}, language = {en} } @inproceedings{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 = {Conference on Modelling Fluid Flow (CMFF'18), The 17th International Conference on Fluid Flow Technologies Budapest, Hungary, September 4-7, 2018}, booktitle = {Conference on Modelling Fluid Flow (CMFF'18), The 17th International Conference on Fluid Flow Technologies Budapest, Hungary, September 4-7, 2018}, pages = {8}, abstract = {The One-Dimensional Turbulence (ODT) model is applied to reactive flows in open and closed systems represented by a lifted jet flame in a vitiated coflow, and a constant volume autoignition configuration, respectively. ODT is a one-dimensional model for turbulent flow simulations, which uses a stochastic formulation to represent the effcts of turbulent advection. Diffusion and reaction effcts along the ODT domain are considered by deterministic evolution equations. This work is an effort to verify the applicability and effiency of the model for open and closed systems. In the open system case, ODT results are compared against experimental results of a lifted methane/air jet flame detailed in the work of Cabra et al. [1]. In the closed system case, a periodic, constant volume domain is used to investigate the sensitivity of the ignition evolution to initial temperature and composition inhomogeneities of a lean n-heptane/air mixture. In the latter context, ODT results are compared to DNS results from Luong et al. [2]. Results for the jet and constant volume configuration show a reasonable match with the experimental and DNS data, considering the reduced order of the model and the underlying assumptions for each case. At the jet configuration, a dependence of the flame evolution on the turbulence intensity parameter can be seen. For the closed system, initial temperature and composition inhomogeneities allow a mitigation of the undesirable rapid pressure rise.}, language = {en} } @inproceedings{MedinaMendezSchmidt, author = {Medina M{\´e}ndez, Juan Ali and Schmidt, Heiko}, title = {One-Dimensional Turbulence investigation of incompressible and low Mach number variable density pipe-flow}, 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 = {285 -- 286}, language = {en} } @inproceedings{MedinaMendezSchmidt, author = {Medina M{\´e}ndez, Juan Ali and Schmidt, Heiko}, title = {Application of ODT to constant volume autoignition problems}, series = {88th Annual Meeting of the International Association of Applied Mathematics and Mechanics March 6-10, 2017 Weimar, Germany, Book of abstracts}, booktitle = {88th Annual Meeting of the International Association of Applied Mathematics and Mechanics March 6-10, 2017 Weimar, Germany, Book of abstracts}, publisher = {GAMM}, pages = {S. 360}, language = {en} } @misc{GlaweMedinaMendezSchmidt, author = {Glawe, Christoph and Medina M{\´e}ndez, Juan Ali and Schmidt, Heiko}, title = {IMEX based Multi-Scale Time Advancement in ODTLES,}, series = {Zeitschrift f{\"u}r angewandte Mathematik und Mechanik}, volume = {98}, journal = {Zeitschrift f{\"u}r angewandte Mathematik und Mechanik}, number = {11}, issn = {1521-4001}, doi = {10.1002/zamm.201800098}, pages = {1907 -- 1923}, 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{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} } @misc{MedinaMendezSchmidt, author = {Medina M{\´e}ndez, Juan Ali and Schmidt, Heiko}, title = {One-dimensional turbulence investigation of incompressible and low Mach number variable density pipe-flow}, 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.201800090}, pages = {2}, 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{MedinaMendezSchmidt, author = {Medina M{\´e}ndez, Juan Ali and Schmidt, Heiko}, title = {Application of ODT to constant volume autoignition problems}, series = {Proceedings in Applied Mathematics and Mechanics}, volume = {17}, journal = {Proceedings in Applied Mathematics and Mechanics}, number = {1}, issn = {1617-7061}, doi = {10.1002/pamm.201710291}, pages = {643 -- 644}, abstract = {The One-Dimensional Turbulence (ODT) model is applied to a constant volume configuration by means of a periodic, one-dimensional domain subject to randomized ensemble members with initial inhomogeneous temperature fields and homogeneous mass fraction profiles. The multidimensional turbulent interactions in the flow are modeled by the separate implementation of turbulent advection and the diffusion-reaction processes, neglecting the mean advection of the system. On one hand, turbulent advection is modeled by means of the eddy events defined within the framework of ODT; on the other hand, the diffusion-reaction system is solved by means of the Zero-Mach limit conservation equations discretized with a 1D Finite Volume Method (FVM). The treatment is specialized in this work to constant volume systems. Due to the inherent stiffness of the diffusion-reaction system, an operator splitting approach is also included in the formulation. Results for n-Heptane chemistry comprising the temporal evolution of the heat release rate, pressure and normalized density-weighted displacement speed are shown and compared to DNS results from Yoo et al. [Combust. Flame 158 (2011) 1727-1741], in terms of individual ensemble members and mean ensemble behavior. The results show that it is possible to obtain reasonably good results in comparison to the DNS if an appropriate set of initial conditions is used. Furthermore, it is shown that the model uncertainty is negligible in comparison to the ensemble standard deviation introduced by randomized initial conditions. Overall, this work introduces the framework for constant volume autoignition in ODT and shows its efficiency for complex chemistry simulations.}, language = {en} } @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} }