@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} }