ALESSANDRO CECI

Dottore di ricerca

ciclo: XXXVI


co-supervisore: Professor Sergio Pirozzoli

Titolo della tesi: Numerical tools for high-fidelity simulation of shock/boundary layer interactions

Shock-wave/turbulent-boundary-layer interactions (SBLIs) are a characteristic phenomenon in numerous high-speed aerodynamic flows. They are frequently encountered in external flows, including transonic and supersonic airfoils, aerodynamic appendages, wing-body junctions, as well as in internal flows, like supersonic engine inlets, compressors and turbines. More broadly, SBLIs occur whenever a shock wave encounters a turbulent boundary layer developing on a solid surface. The impact of a shock on a boundary layer typically results in substantial flow separation, which can lead to significant decreases in performance. Efficiency loss of aerodynamic surfaces, structural vibrations induced by wall pressure fluctuations, and localized heat transfer peaks are common examples of undesired effects stemming from SBLIs. Consequently, the study and the understanding of this flow phenomenon has gained a lot of interest in the aeronautic/aerospace research field. This work concentrates on both the numerical and physical aspects of SBLIs. In the first part, we elucidate the numerical framework utilized to simulate these interactions using Direct Numerical Simulations (DNS), both in Cartesian and curvilinear coordinates. Special emphasis has been placed on the handling of convective terms, which have been reformulated into a convenient split form ensuring the discrete preservation of total kinetic energy. Subsequently, various DNS of canonical flows are performed, including turbulent boundary layers, oblique SBLIs and compression corners. Our primary focus is on addressing technical aspects for state-of-the-art numerical simulations. This encompasses the adaptation of classical synthetic turbulence prescription at the inflow of the computational domain, and the implementation of appropriate grid stretching functions in the wall-normal direction. Another significant aspect is the analysis of low-frequency unsteadiness in SBLI configurations involving the presence of cross-flow. Notably, we show that, when the boundary layer meets the shock with a non-zero sweep angle, the typical low-frequency unsteadiness can shift to higher tones following a specific relationship dependent on the sweep angle and on large-scale structures at the foot of the reflected shock. In conclusion, we present the validation results of the new code in curvilinear coordinates for a supersonic compression corner, along with the ongoing research projects that incorporate it.

Produzione scientifica

11573/1703805 - 2024 - FLEW: A DNS Solver for Compressible Flows in Generalized Curvilinear Coordinates
Soldati, Giulio; Ceci, Alessandro; Pirozzoli, Sergio - 01a Articolo in rivista
rivista: AEROTECNICA MISSILI E SPAZIO ([Cham]: Springer International Publishing Milano: Tamburini Rome Italy-Pisa: Associazione Italiana di Aeronautica e Astronautica) pp. - - issn: 0365-7442 - wos: (0) - scopus: (0)

11573/1687090 - 2023 - High-fidelity simulation of shock-wave/boundary layer interactions
Ceci, A. - 04b Atto di convegno in volume
congresso: III Aerospace PhD-Days (Bertinoro)
libro: Aerospace Science and Engineering – III Aerospace PhD-Days - (9781644902677)

11573/1666225 - 2023 - On low-frequency unsteadiness in swept shock wave–boundary layer interactions
Ceci, Alessandro; Palumbo, Andrea; Larsson, Johan; Pirozzoli, Sergio - 01a Articolo in rivista
rivista: JOURNAL OF FLUID MECHANICS (London: Cambridge University Press.) pp. - - issn: 0022-1120 - wos: WOS:000922319300001 (5) - scopus: 2-s2.0-85147089282 (7)

11573/1682382 - 2023 - Natural grid stretching for DNS of compressible wall-bounded flows
Ceci, Alessandro; Pirozzoli, Sergio - 01a Articolo in rivista
rivista: JOURNAL OF COMPUTATIONAL PHYSICS: X (New York: Elsevier Inc.) pp. - - issn: 2590-0552 - wos: (0) - scopus: 2-s2.0-85160838576 (0)

11573/1703815 - 2023 - Development of a DNS solver for compressible flows in generalized curvilinear coordinates
Soldati, Giulio; Ceci, Alessandro; Pirozzoli, Sergio - 04b Atto di convegno in volume
congresso: Aeronautics and Astronautics - AIDAA XXVII International Congress (Padova)
libro: Aeronautics and Astronautics - AIDAA XXVII International Congress - ()

11573/1658425 - 2022 - Direct numerical simulations of turbulent pipe flow at high Reynolds number
Ceci, A.; Pirozzoli, S.; Romero, J.; Fatica, M.; Verzicco, R.; Orlandi, P. - 01a Articolo in rivista
rivista: PHYSICAL REVIEW FLUIDS (American Physical Society) pp. - - issn: 2469-990X - wos: WOS:000884692900008 (0) - scopus: 2-s2.0-85143901511 (0)

11573/1657627 - 2022 - Numerical tripping of high-speed turbulent boundary layers
Ceci, A; Palumbo, A; Larsson, J; Pirozzoli, S - 01a Articolo in rivista
rivista: THEORETICAL AND COMPUTATIONAL FLUID DYNAMICS (Springer Verlag Germany:Tiergartenstrasse 17, D 69121 Heidelberg Germany:011 49 6221 3450, EMAIL: g.braun@springer.de, INTERNET: http://www.springer.de, Fax: 011 49 6221 345229) pp. 865-886 - issn: 0935-4964 - wos: WOS:000840246200001 (7) - scopus: 2-s2.0-85135872891 (9)

11573/1657626 - 2022 - Reynolds number effects and outer similarity of pressure fluctuations in turbulent pipe flow
Yu, M; Ceci, A; Pirozzoli, S - 01a Articolo in rivista
rivista: INTERNATIONAL JOURNAL OF HEAT AND FLUID FLOW (Butterworth Heinemann Publ:200 Wheeler Road:Burlington, MA 01803:(800)366-2665, INTERNET: http://www.butterworths.co.za, Fax: (617)933-6333 ELSEVIER SCIENCE INC, 360 PARK AVE SOUTH, NEW YORK, USA, NY, 10010-1710) pp. - - issn: 0142-727X - wos: WOS:000830082900003 (2) - scopus: 2-s2.0-85130164756 (2)

11573/1657625 - 2021 - Computational analysis of the indirect combustion noise generation mechanism in a nozzle guided vane in transonic operating conditions
Ceci, Alessandro; Gojon, Romain; Mihaescu, Mihai - 01a Articolo in rivista
rivista: JOURNAL OF SOUND AND VIBRATION (Elsevier Science Limited:Oxford Fulfillment Center, PO Box 800, Kidlington Oxford OX5 1DX United Kingdom:011 44 1865 843000, 011 44 1865 843699, EMAIL: asianfo@elsevier.com, tcb@elsevier.co.UK, INTERNET: http://www.elsevier.com, http://www.elsevier.com/locate/shpsa/, Fax: 011 44 1865 843010) pp. - - issn: 0022-460X - wos: WOS:000616286500003 (1) - scopus: 2-s2.0-85098886979 (1)

11573/1657624 - 2019 - Large eddy simulations for indirect combustion noise assessment in a nozzle guide vane passage
Ceci, Alessandro; Gojon, Romain; Mihaescu, Mihai - 01a Articolo in rivista
rivista: FLOW TURBULENCE AND COMBUSTION (Kluwer Academic Publishers:Journals Department, PO Box 322, 3300 AH Dordrecht Netherlands:011 31 78 6576050, EMAIL: frontoffice@wkap.nl, kluweronline@wkap.nl, INTERNET: http://www.kluwerlaw.com, Fax: 011 31 78 6576254) pp. 299-311 - issn: 1386-6184 - wos: WOS:000465588800004 (5) - scopus: 2-s2.0-85052594186 (6)

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