--- _id: '1216' abstract: - lang: eng text: 'A framework fo r extracting features in 2D transient flows, based on the acceleration field to ensure Galilean invariance is proposed in this paper. The minima of the acceleration magnitude (a superset of acceleration zeros) are extracted and discriminated into vortices and saddle points, based on the spectral properties of the velocity Jacobian. The extraction of topological features is performed with purely combinatorial algorithms from discrete computational topology. The feature points are prioritized with persistence, as a physically meaningful importance measure. These feature points are tracked in time with a robust algorithm for tracking features. Thus, a space-time hierarchy of the minima is built and vortex merging events are detected. We apply the acceleration feature extraction strategy to three two-dimensional shear flows: (1) an incompressible periodic cylinder wake, (2) an incompressible planar mixing layer and (3) a weakly compressible planar jet. The vortex-like acceleration feature points are shown to be well aligned with acceleration zeros, maxima of the vorticity magnitude, minima of the pressure field and minima of λ2.' acknowledgement: "The authors acknowledge funding of the German Re-\r\nsearch Foundation \ (DFG) via the Collaborative Re-\r\nsearch Center (SFB 557) \\Control of \ Complex Turbu-\r\nlent Shear Flows\" and the Emmy Noether Program.\r\nFurther \ funding was provided by the Zuse Institute\r\nBerlin (ZIB), the DFG-CNRS \ research group \\Noise\r\nGeneration in Turbulent Flows\" (2003{2010), the Chaire\r\nd'Excellence 'Closed-loop control of turbulent shear ows\r\nusing reduced-order models' (TUCOROM) of the French\r\nAgence Nationale de la Recherche (ANR), and the Eu-\r\nropean Social \ Fund (ESF App. No. 100098251). We\r\nthank the Ambrosys Ltd. Society \ for Complex Sys-\r\ntems Management and the Bernd R. Noack Cybernet-\r\nics \ Foundation for additional support. A part of this\r\nwork was performed using HPC resources from GENCI-[CCRT/CINES/IDRIS] supported by the Grant 2011-\r\n[x2011020912" author: - first_name: Jens full_name: Kasten, Jens last_name: Kasten - first_name: Jan full_name: Reininghaus, Jan id: 4505473A-F248-11E8-B48F-1D18A9856A87 last_name: Reininghaus - first_name: Ingrid full_name: Hotz, Ingrid last_name: Hotz - first_name: Hans full_name: Hege, Hans last_name: Hege - first_name: Bernd full_name: Noack, Bernd last_name: Noack - first_name: Guillaume full_name: Daviller, Guillaume last_name: Daviller - first_name: Marek full_name: Morzyński, Marek last_name: Morzyński citation: ama: Kasten J, Reininghaus J, Hotz I, et al. Acceleration feature points of unsteady shear flows. Archives of Mechanics. 2016;68(1):55-80. apa: Kasten, J., Reininghaus, J., Hotz, I., Hege, H., Noack, B., Daviller, G., & Morzyński, M. (2016). Acceleration feature points of unsteady shear flows. Archives of Mechanics. Polish Academy of Sciences Publishing House. chicago: Kasten, Jens, Jan Reininghaus, Ingrid Hotz, Hans Hege, Bernd Noack, Guillaume Daviller, and Marek Morzyński. “Acceleration Feature Points of Unsteady Shear Flows.” Archives of Mechanics. Polish Academy of Sciences Publishing House, 2016. ieee: J. Kasten et al., “Acceleration feature points of unsteady shear flows,” Archives of Mechanics, vol. 68, no. 1. Polish Academy of Sciences Publishing House, pp. 55–80, 2016. ista: Kasten J, Reininghaus J, Hotz I, Hege H, Noack B, Daviller G, Morzyński M. 2016. Acceleration feature points of unsteady shear flows. Archives of Mechanics. 68(1), 55–80. mla: Kasten, Jens, et al. “Acceleration Feature Points of Unsteady Shear Flows.” Archives of Mechanics, vol. 68, no. 1, Polish Academy of Sciences Publishing House, 2016, pp. 55–80. short: J. Kasten, J. Reininghaus, I. Hotz, H. Hege, B. Noack, G. Daviller, M. Morzyński, Archives of Mechanics 68 (2016) 55–80. date_created: 2018-12-11T11:50:46Z date_published: 2016-01-01T00:00:00Z date_updated: 2021-01-12T06:49:09Z day: '01' department: - _id: HeEd intvolume: ' 68' issue: '1' language: - iso: eng main_file_link: - open_access: '1' url: http://am.ippt.pan.pl/am/article/viewFile/v68p55/pdf month: '01' oa: 1 oa_version: Published Version page: 55 - 80 publication: Archives of Mechanics publication_status: published publisher: Polish Academy of Sciences Publishing House publist_id: '6118' quality_controlled: '1' scopus_import: 1 status: public title: Acceleration feature points of unsteady shear flows type: journal_article user_id: 3E5EF7F0-F248-11E8-B48F-1D18A9856A87 volume: 68 year: '2016' ...