000165008 001__ 165008 000165008 005__ 20251204150238.0 000165008 0247_ $$2doi$$a10.1063/1.4884555 000165008 0248_ $$2sideral$$a87663 000165008 037__ $$aART-2014-87663 000165008 041__ $$aeng 000165008 100__ $$aCifuentes,L.$$uUniversidad de Zaragoza 000165008 245__ $$aLocal flow topologies and scalar structures in a turbulent premixed flame 000165008 260__ $$c2014 000165008 5060_ $$aAccess copy available to the general public$$fUnrestricted 000165008 5203_ $$aA three-dimensional direct numerical simulation of a propagating turbulent premixed flame is performed using one-step Arrhenius model chemistry. The interaction of the flame thermochemical processes with the local geometries of the scalar field and flow topologies is studied. Four regions (“fresh reactants,” “preheating,” “burning,” and “hot products”), characterized by their reaction rate and mass fraction values, are examined. Thermochemical processes in the “preheating” and “burning” regions smooth out highly contorted iso-scalar surfaces, present in the “fresh reactants,” and annihilate large curvatures. Positive volumetric dilatation rates, −P = ∇ · u, display maxima for elliptic concave and minima for convex scalar micro-structures. Constant average tangential strain rates, aT, with large fluctuations, occur throughout the flow domain, whereas normal strain rates, aN, follow the trends of volumetric dilatation rates. Focal topologies, present in the “fresh reactants,” tend to disappear in favor of nodal structures as moving towards the “hot products.” The vorticity vector is predominantly tangential to the iso-scalar surfaces. The Unstable Node/Saddle/Saddle and Stable Focus/Stretching topologies, present in the “fresh reactants,” correlate with large values of aN and aT providing hints on the flow topologies fostering scalar mixing. 000165008 540__ $$9info:eu-repo/semantics/openAccess$$aAll rights reserved$$uhttp://www.europeana.eu/rights/rr-f/ 000165008 590__ $$a2.031$$b2014 000165008 591__ $$aMECHANICS$$b25 / 136 = 0.184$$c2014$$dQ1$$eT1 000165008 591__ $$aPHYSICS, FLUIDS & PLASMAS$$b13 / 31 = 0.419$$c2014$$dQ2$$eT2 000165008 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion 000165008 700__ $$0(orcid)0000-0002-2267-8598$$aDopazo,C.$$uUniversidad de Zaragoza 000165008 700__ $$0(orcid)0000-0003-3908-0493$$aMartin,J.$$uUniversidad de Zaragoza 000165008 700__ $$aJimenez,C. 000165008 7102_ $$15001$$2600$$aUniversidad de Zaragoza$$bDpto. Ciencia Tecnol.Mater.Fl.$$cÁrea Mecánica de Fluidos 000165008 773__ $$g26, 6 (2014), 065108 [25 pp.]$$pPhys. fluids$$tPhysics of Fluids$$x1070-6631 000165008 8564_ $$s3205986$$uhttps://zaguan.unizar.es/record/165008/files/texto_completo.pdf$$yVersión publicada 000165008 8564_ $$s897054$$uhttps://zaguan.unizar.es/record/165008/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada 000165008 909CO $$ooai:zaguan.unizar.es:165008$$particulos$$pdriver 000165008 951__ $$a2025-12-04-14:39:13 000165008 980__ $$aARTICLE