GIACOMO DELLA POSTA

PhD Graduate

PhD program:: XXXIV


supervisor: Matteo Bernardini
advisor: Paolo Gualtieri

Thesis title: A Novel High-Fidelity Two-Way Coupling Model for Fluid-Structure Interaction in Wind Energy

To increase the attractiveness of wind energy, wind turbines are continuously scaling up, with diameters now exceeding 200 m. If on the one hand, this trend guarantees an increased power production, on the other hand, it imposes harsher aerodynamical and structural requirements – on the blades in particular – that are difficult to characterise. In particular, the significant size of the state-of-the-art wind turbines suggests a more relevant Fluid-Structure Interaction (FSI) that could alter dramatically the operating life of the full machine. Given the difficulties and the costs of measuring the phenomena occurring at significant scales, researchers advocate the development of high-fidelity numerical models exploiting Computational Fluid and Structural Dynamics (CFD-CSD models). For this reason, in this work we present a novel FSI model for wind turbines combining our Large Eddy Simulation (LES) fluid solver with a modal beam-like structural solver. In the first part of the work, we present the details of our FSI methodology, and we analyse the effects of different coupling conditions. A loose algorithm couples the Actuator Line Model (ALM), which represents the blades in the fluid domain by means of body forces, with the structural model, which represents the flexural and torsional deformations. For a reference utility-scale wind turbine, we compare the results of three sets of simulations. Firstly, we consider one-way coupled simulations where only the fluid solver provides the structural solver with the aerodynamic loads; then, we consider two-way coupled simulations where the structural feedback to the fluid solver is made of the out-of-plane and in-plane bending deformation velocities only; finally, we add to the feedback also the torsional deformation. However, to accurately reproduce the airloads, one should notice that the blades in particular are subjected to many relevant sources of unsteadiness, e.g. tower shadowing, yawed and waked conditions, environmental effects. Therefore, researchers have questioned the use of steady aerodynamics in the numerical fluid and aeroelastic models used in wind energy that do not have the sufficient resolution to solve the flow close to the blade, arguing that the use of tabulated airfoil coefficients could neglect effects that alter the estimation of the turbine behaviour. Different unsteady aerodynamics models have been proposed to account for these effects but have been mainly implemented in low-fidelity engineering models, which lack the complete capability of describing the multiscale and multi-physics phenomena characterising the wind turbine. For this reason, in the second part of the work, a 2D unsteady aerodynamics model is implemented in the sectional estimation of the airloads of the Actuator Line Model. At each section of the blade, a semi-empirical Beddoes-Leishman model includes the effects of additional noncirculatory terms, unsteady trailing edge separation and dynamic stall in the dynamic evaluation of the aerodynamic coefficients of the airfoils, used to determine the ALM body forces. Different inflow conditions and aeroelastic behaviours are examined with the aim of examining the effects of the model, and thus of providing a deeper insight into the unsteady characterisation of large wind turbines by means of a high-fidelity CFD-CSD model.

Research products

11573/1700234 - 2024 - Direct numerical simulation of boundary layers over microramps. mach number effects
Della Posta, G; Fratini, M; Salvadore, F; Bernardini, M - 01a Articolo in rivista
paper: AIAA JOURNAL ([New York, etc.] American Institute of Aeronautics and Astronautics.) pp. 542-556 - issn: 0001-1452 - wos: WOS:001087848700001 (0) - scopus: 2-s2.0-85185258201 (0)

11573/1709167 - 2023 - The effect of the tower’s modeling on the aero-elastic response of the NREL 5 MW wind turbine
Bernardi, Claudio; Della Posta, Giacomo; De Palma, Pietro; Leonardi, Stefano; Bernardoni, Federico; Bernardini, Matteo; Cherubini, Stefania - 04b Atto di convegno in volume
conference: Wake Conference 2023 (Visby, Sweden)
book: Journal of Physics: Conference Series - ()

11573/1714155 - 2023 - STREAmS-2.0: Supersonic turbulent accelerated Navier-Stokes solver version 2.0
Bernardini, M.; Modesti, D.; Salvadore, F.; Sathyanarayana, S.; Della Posta, G.; Pirozzoli, S. - 01a Articolo in rivista
paper: COMPUTER PHYSICS COMMUNICATIONS (Amsterdam: Elsevier BV) pp. 108644- - issn: 0010-4655 - wos: WOS:000995570700001 (15) - scopus: 2-s2.0-85145780653 (19)

11573/1714152 - 2023 - Unsteadiness characterisation of shock wave/turbulent boundary-layer interaction at moderate Reynolds number
Bernardini, Matteo; Della Posta, Giacomo; Salvadore, Francesco; Martelli, Emanuele - 01a Articolo in rivista
paper: JOURNAL OF FLUID MECHANICS (London: Cambridge University Press.) pp. - - issn: 0022-1120 - wos: WOS:000911170600001 (15) - scopus: 2-s2.0-85146148885 (16)

11573/1697223 - 2023 - CFD Analysis of the Lateral Sloshing Phenomenon inside an Aerospace LH2 Cryogenic Tank
Cimini, Matteo; Rossetti, Francesca; Della Posta, Giacomo; Stella, Fulvio; Bernardini, Matteo - 04b Atto di convegno in volume
conference: Aerospace Europe Conference 2023 – 10ᵀᴴ EUCASS – 9ᵀᴴ CEAS (Lausanne, Switzerland)
book: Aerospace Europe Conference 2023 – 10ᵀᴴ EUCASS – 9ᵀᴴ CEAS - ()

11573/1714157 - 2023 - Direct numerical simulation of supersonic boundary layers over a microramp: Effect of the Reynolds number
Della Posta, G.; Blandino, M.; Modesti, D.; Salvadore, F.; Bernardini, M. - 01a Articolo in rivista
paper: JOURNAL OF FLUID MECHANICS (London: Cambridge University Press.) pp. - - issn: 0022-1120 - wos: WOS:001120973400001 (2) - scopus: 2-s2.0-85177987651 (4)

11573/1683763 - 2023 - A DNS study on the Mach number effect for a supersonic microramp
Della Posta, Giacomo; Fratini, Marco; Salvadore, Francesco; And Bernardini, Matteo - 04b Atto di convegno in volume
conference: 57th 3AF International Conference on Applied Aerodynamics (Bordeaux)
book: 57th 3AF International Conference on Applied Aerodynamics - ()

11573/1683762 - 2023 - High-fidelity simulations of the aeroacoustic environment of the VEGA launch vehicle at lift-off
Della Posta, Giacomo; Martelli, Emanuele; Stella, Fulvio; Barbagallo, Daniele; Neri, Agostino; Salvadore, Francesco; Bernardini, Matteo - 01a Articolo in rivista
paper: COMPUTERS & FLUIDS (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: 0045-7930 - wos: WOS:001027645800001 (2) - scopus: 2-s2.0-85163105701 (3)

11573/1714156 - 2023 - Direct numerical simulation of a microramp in a high-Reynolds number supersonic turbulent boundary layer
Salvadore, F.; Memmolo, A.; Modesti, D.; Della Posta, G.; Bernardini, M. - 01a Articolo in rivista
paper: PHYSICAL REVIEW FLUIDS (American Physical Society) pp. - - issn: 2469-990X - wos: WOS:001110706600004 (2) - scopus: 2-s2.0-85178033002 (2)

11573/1644530 - 2022 - A two-way coupling method for the study of aeroelastic effects in large wind turbines
Della Posta, G.; Leonardi, S.; Bernardini, M. - 01a Articolo in rivista
paper: RENEWABLE ENERGY (Oxford UK: Elsevier Science Limited) pp. 971-992 - issn: 0960-1481 - wos: WOS:000793564900003 (19) - scopus: 2-s2.0-85127918958 (21)

11573/1661546 - 2022 - Large eddy simulations of a utility-scale horizontal axis wind turbine including unsteady aerodynamics and fluid-structure interaction modelling
Della Posta, G.; Leonardi, S.; Bernardini, M. - 01a Articolo in rivista
paper: WIND ENERGY (John Wiley & Sons Limited:1 Oldlands Way, Bognor Regis, P022 9SA United Kingdom:011 44 1243 779777, EMAIL: cs-journals@wiley.co.uk, INTERNET: http://www.wiley.co.uk, Fax: 011 44 1243 843232) pp. 98-125 - issn: 1095-4244 - wos: WOS:000881757100001 (5) - scopus: 2-s2.0-85141970898 (5)

11573/1644541 - 2021 - A novel two-way coupling method for the study of the aeroelasticity of wind turbines in a Large Eddy Simulation framework
Della Posta, Giacomo; Ciri, Umberto; Leonardi, Stefano; Bernardini, Matteo - 04b Atto di convegno in volume
conference: 14th European conference on turbomachinery fluid dynamics and thermodynamics (ETC 14) (Gdansk, Poland)
book: 14th European conference on turbomachinery fluid dynamics and thermodynamics - ()

11573/1317857 - 2019 - Enhanced delayed DES of shock wave/boundary layer interaction in a planar transonic nozzle
Della Posta, G.; Martelli, E.; Ciottoli, P. P.; Stella, F.; Bernardini, M. - 01a Articolo in rivista
paper: 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. 359-365 - issn: 0142-727X - wos: WOS:000471084900028 (2) - scopus: 2-s2.0-85065553592 (3)

11573/1681891 - 2018 - Enhanced Delayed DES of shock wave/boundary layer interaction in a planar transonic nozzle
Della Posta, G.; Martelli, E.; Ciottoli, P. P.; Stella, F.; Bernardini, M. - 04b Atto di convegno in volume
conference: 9th International symposium on turbulence heat and mass transfer (Rio de Janeiro, BRAZIL)
book: Proceedings of the international symposium on turbulence, heat and mass transfer - (978-1-56700-468-7; 978-1-56700-467-0)

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