Academic Journal

Investigation of the turbulent flame structure and topology at different Karlovitz numbers using the tangential stretching rate index

التفاصيل البيبلوغرافية
العنوان: Investigation of the turbulent flame structure and topology at different Karlovitz numbers using the tangential stretching rate index
المؤلفون: Manias, Dimitris M., Tingas, Alexandros, Hernandez Perez, Francisco, Malpica Galassi, Riccardo, Ciottoli, Pietro P., Valorani, Mauro, Im, Hong G.
المساهمون: Clean Combustion Research Center, Computational Reacting Flow Laboratory (CRFL), Mechanical Engineering Program, Physical Science and Engineering (PSE) Division, Department of Mechanics, School of Applied Mathematical and Physical Sciences, National Technical University, Athens 15773, Greece, Mechanical and Aerospace Engineering Department, Sapienza University, Rome 00184, Italy
بيانات النشر: Elsevier BV
سنة النشر: 2018
المجموعة: King Abdullah University of Science and Technology: KAUST Repository
مصطلحات موضوعية: CSP, TSR, Extreme combustion, Turbulent flames, High Karlovitz number, Flame topology
الوصف: Turbulent premixed flames at high Karlovitz numbers exhibit highly complex structures in different reactive scalar fields to the extent that the definition of the flame front in an unambiguous manner is not straightforward. This poses a significant challenge in characterizing the observable turbulent flame behaviour such as the flame surface density, turbulent burning velocity, and so on. Turbulent premixed flames are reactive flows involving physical and chemical processes interacting over a wide range of time scales. By recognizing the multi-scale nature of reactive flows, we analyze the topology and structure of two direct numerical simulation cases of turbulent H2/air premixed flames, in the thin reaction zone and distributed combustion regimes, using tools derived from the computational singular perturbation (CSP) method and augmented by the tangential stretching rate (TSR) analysis. CSP allows to identify the local time scale decomposition of the multi-scale problem in its slow and fast components, while TSR allows to identify the most energetic time scale during both the explosive and dissipative regime of the reactive flow dynamics together with the identification of the flame front in an unambiguous manner. Before facing the complexity of the turbulent flow regime, we carry out a preliminary analysis of a one-dimensional laminar premixed flame in view of highlighting similarities and differences between laminar and turbulent cases. Subsequently, it is shown that the TSR metric provides a reliable way to identify the turbulent flame topologies. ; This work was sponsored by competitive research funding from King Abdullah University of Science and Technology (KAUST). MV acknowledges the support of the Italian Ministry of University and Research (MIUR).
نوع الوثيقة: article in journal/newspaper
وصف الملف: application/pdf
اللغة: unknown
تدمد: 0010-2180
Relation: https://www.sciencedirect.com/science/article/pii/S0010218018305042; Manias DM, Tingas E-A, Hernández Pérez FE, Malpica Galassi R, Paolo Ciottoli P, et al. (2019) Investigation of the turbulent flame structure and topology at different Karlovitz numbers using the tangential stretching rate index. Combustion and Flame 200: 155–167. Available: http://dx.doi.org/10.1016/j.combustflame.2018.11.023.; Combustion and Flame; http://hdl.handle.net/10754/630124
DOI: 10.1016/j.combustflame.2018.11.023
الاتاحة: http://hdl.handle.net/10754/630124
https://doi.org/10.1016/j.combustflame.2018.11.023
Rights: NOTICE: this is the author’s version of a work that was accepted for publication in Combustion and Flame. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Combustion and Flame, [, , (2018-11-30)] DOI:10.1016/j.combustflame.2018.11.023 . © 2018. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/
رقم الانضمام: edsbas.2D2D8FFF
قاعدة البيانات: BASE