TY - GEN A1 - Medina Méndez, Juan Ali A1 - Schmidt, Heiko A1 - Mauß, Fabian A1 - Jozefik, Zoltan T1 - Constant volume n-Heptane autoignition using One-Dimensional Turbulence T2 - Combustion and Flame N2 - 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 … KW - One-Dimensional Turbulence KW - n-Heptane autoignition Y1 - 2018 U6 - https://doi.org/10.1016/j.combustflame.2017.12.015 SN - 0010-2180 VL - 190 SP - 388 EP - 401 ER - TY - CHAP A1 - Starick, Tommy A1 - Medina Méndez, Juan Ali A1 - Schmidt, Heiko T1 - One-Dimensional Turbulence simulations for reactive flows in open and closed systems T2 - Conference on Modelling Fluid Flow (CMFF’18), The 17th International Conference on Fluid Flow Technologies Budapest, Hungary, September 4-7, 2018 N2 - 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. Y1 - 2018 UR - https://www-docs.b-tu.de/fg-stroemungsmodellierung/public/Starick_2018_cmff_final_after_review.pdf ER - TY - CHAP A1 - Medina Méndez, Juan Ali A1 - Schmidt, Heiko T1 - One-Dimensional Turbulence investigation of incompressible and low Mach number variable density pipe-flow T2 - 89th Annual Meeting of the International Association of Applied Mathematics and Mechanics March 19-23, 2018 Munich, Germany, Book of abstracts Y1 - 2018 UR - http://jahrestagung.gamm-ev.de/images/2018/book_of_abstracts.pdf SP - 285 EP - 286 PB - GAMM ER - TY - CHAP A1 - Medina Méndez, Juan Ali A1 - Schmidt, Heiko T1 - Application of ODT to constant volume autoignition problems T2 - 88th Annual Meeting of the International Association of Applied Mathematics and Mechanics March 6-10, 2017 Weimar, Germany, Book of abstracts Y1 - 2017 UR - https://www.tu-ilmenau.de/fileadmin/media/analysis/trunk/170304_BoA_GAMM_2017.pdf SP - S. 360 PB - GAMM ER - TY - GEN A1 - Glawe, Christoph A1 - Medina Méndez, Juan Ali A1 - Schmidt, Heiko T1 - IMEX based Multi-Scale Time Advancement in ODTLES, T2 - Zeitschrift für angewandte Mathematik und Mechanik KW - ODTLES Y1 - 2018 U6 - https://doi.org/10.1002/zamm.201800098 SN - 1521-4001 VL - 98 IS - 11 SP - 1907 EP - 1923 ER - TY - GEN A1 - Lignell, David O. A1 - Lansinger, Victoria B. A1 - Medina Méndez, Juan Ali A1 - Klein, Marten A1 - Kerstein, Alan R. A1 - Schmidt, Heiko A1 - Fistler, Marco A1 - Oevermann, Michael T1 - One-dimensional turbulence modeling for cylindrical and spherical flows: model formulation and application T2 - Theoretical and Computational Fluid Dynamics N2 - 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. KW - Cylindrical ODT Y1 - 2018 U6 - https://doi.org/10.1007/s00162-018-0465-1 SN - 0935-4964 SN - 1432-2250 VL - 32 IS - 4 SP - 495 EP - 520 ER - TY - GEN A1 - Starick, Tommy A1 - Medina Méndez, Juan Ali A1 - Schmidt, Heiko T1 - One-Dimensional Turbulence simulations for reactive flows in open and closed systems T2 - Technische Mechanik Y1 - 2019 U6 - https://doi.org/10.24352/UB.OVGU-2019-015 VL - 39 IS - 1 SP - 162 EP - 174 ER - TY - GEN A1 - Medina Méndez, Juan Ali A1 - Schmidt, Heiko T1 - One‐dimensional turbulence investigation of incompressible and low Mach number variable density pipe‐flow T2 - Proceedings in Applied Mathematics and Mechanics : PAMM KW - ODT KW - pipe flow Y1 - 2018 U6 - https://doi.org/10.1002/pamm.201800090 SN - 1617-7061 VL - 18 IS - 1 ER - TY - CHAP A1 - Medina Méndez, Juan Ali A1 - Glawe, Christoph A1 - Starick, Tommy A1 - Schöps, Mark Simon A1 - Schmidt, Heiko T1 - IMEX-ODTLES: A multi-scale and stochastic approach for highly turbulent flows T2 - 90th Annual Meeting of the International Association of Applied Mathematics and Mechanics February 18-22, 2019 Vienna, Austria, Abstract book Y1 - 2019 UR - https://jahrestagung.gamm-ev.de/images/2019/Photos/GAMM2019_BookofAbstracts.pdf SN - 978-3-903024-84-7 PB - TU-Verlag CY - Wien ER - TY - GEN A1 - Rakhi, Rakhi A1 - Klein, Marten A1 - Medina Méndez, Juan Ali A1 - Schmidt, Heiko T1 - One-dimensional turbulence modelling of incompressible temporally developing turbulent boundary layers with comparison to DNS T2 - Journal of Turbulence N2 - 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. KW - one-dimensional turbulence KW - stochastic modeling KW - turbulent boundary layers Y1 - 2019 U6 - https://doi.org/10.1080/14685248.2019.1674859 SN - 1468-5248 VL - 20 IS - 8 SP - 506 EP - 543 ER -