|Dr. Luca Greco has carried out a continuous research activity from 2002 to nowadays. He has focused on the development of theoretical formulations and numerical methods aimed at preliminary design and efficient simulation of aeronautical and marine rotary wing systems as well as renewable energy rotating devices. Although academic in nature, the results of this research activity address engineering applications strictly related to the topics of several ongoing research projects where the writer is involved at CNR-INSEAN in partnership with other Research Institutes, Industrial customers and Universities worldwide. After the Master of Science Degree in Mechanical Engineering, he has worked with his supervisor at Roma Tre University on the development of unsteady aerodynamics solvers for the aeroelastic analysis of screw propulsors. Since 2003 he is working at Marine Technology Research Institute (CNR-INSEAN). As aResearch Consultant and fixed term Researcher firstly, and as a Permanent Researcher since 2009, his activity has focused on the development of theoretical models and numerical algorithms for the hydrodynamic analysis of marine propulsors. Specifically, he has addressed complex screw propulsors characterized by strong hydrodynamic and structural interactions among fixed and rotating parts. During the period from 2004 and 2007, the research activity Dr. Luca Greco has been carried out in cooperation with Roma Tre University through his PhD work that has been successfully defended in 2008. Since 2005, his research activity has increasingly focused on rotating blades renewable energy devices with the aim of transferring the experience gained in the aeronautical and marine field to wind and marine currents turbines. In this framework, the activity of the writer addresses theoretical/numerical models for the aero/hydroelastic analysis of wind and marine currents turbines aimed at the development of a comprehensive numerical tool for the prediction of the aero/hydroelastic and aero/hydroacoustic behaviour of vertical and horizontal axis turbines.|
The prediction of rotor/propeller performance and the characterization of the flowfield downstream are some of the research branches that can be addressed through unsteady potential aero/hydrodynamic formulations for three-dimensional (3D) lifting bodies, solved by the Boundary Element Method (BEM). Standard BEM capabilities have been enhanced by including, in particular, several free-wake algorithms for the analysis of the flowfield downstream a rotor/propeller, and to address wake/body interaction in marine and aeronautical propulsors. Moreover, for the analysis of complex multibody configurations of industrial interest, efficient solution methods and parallel computing algorithms have been developed. The developed solvers have been applied in the framework of international EU-funded (STREAMLINE, HYMAR, VIRTUE, SUPERPROP) and national (PRIAMO, SIRENA-prop) research projects to study complex propulsors hydrodynamics as well as to predict (through the application of a Boundary Integral Representation of the velocity field coupled with the Bernoulli Theorem) the noise field generated by naval rotating wings, both in the unbounded fluid domain and in presence of obstacles in the vicinity of the propulsor system.
Beside the ongoing activity on 3D time domain panel methods, the development of theoretical/numerical aerodynamics models for the prediction of the aero/hydroelastic behavior of complex aeronautical/marine propulsors is of primary importance for the writer activity. This research topic has been developed as a natural continuation of the activity of carried out by the writer for his PhD work and is aimed at the technological transfer from the aeronautical/marine field to renewable energy rotating devices. In view of preliminary design purposes, the writer has developed a general approach for the identification of Reduced Order aerodynamics Models (ROM) for the stability eigenanalysis of rotors in axial flow. To this aim, aerodynamic approaches based on a frequency domain BEM solver, on the Theodorsen and Greenberg theories have been applied to propellers and wind turbines. The proposed ROM aerodynamics models have been coupled with with suitable in-house codes for rotating blades structural dynamics analysis. Both a Galërkin modal approach and a Finite Element Method formulation have been considered.
Renewable Energies Rotating devices
This research branch focuses on the analysis of renewable energy generation systems and on the development of new concepts to maximize and control power output capabilities. The scientific activity, performed in the framework of R&D studies (for example, RITmare National Flagship Project) and industrial consultancy activity (for example, Safrema LLC and ENERMAR projects), is focused on wind and current marine turbines. Specifically, horizontal axis wind turbines (WT) performance are investigated from an aeroelastic standpoint through a Finite Element formulation for nonlinear aeroelastic equations of rotating blades undergoing combined flapwise bending, chordwise bending and torsion displacements. Blade structural dynamics model is coupled with Beddoes – Leishman state-space formulation for unsteady sectional aerodynamic loads, including dynamic stall effects. Several CFD – CSD coupling approaches are considered to take into account rotor wake inflow influence on downwash, all based on a 3D Boundary Element Method for the solution of incompressible, potential, attached flows. Widely used semi-empirical approaches to extend sectional steady aerodynamic coefficients to high angles of attack and to model rotating flow effects are also considered to characterize wind turbine operations in deep stall regimes.
The ongoing research activity is also aimed at coupling the developed blade structural model with the fully 3D unsteady panel method. These activities yield a comprehensive aeroelastic platform suitable for the analysis of WT in unsteady flow conditions due to spatial and temporal non-uniformity of the incoming wind/waves and/or in presence of a yaw angle. The proposed WT rotor aerodynamics models have also been integrated into a turbine control system based on the Maximum Power Point Tracking Technique developed by CNR-ISSIA Institute. Differently, R&D hydrodynamic studies on vertical axis marine current turbines (MCT) are mainly focused on the enhancement of turbine performance by CFD simulations, experimental campaigns on hydrodynamic components and development of advanced turbine related systems.
| Marine propulsion|
Marine renewable energy
- Focal point for the research activity of INM within the EERA (European Energy Research Alliance) Wind Energy Joint Programme
- Member of the ISSC (International Ship and Offshore Structures Congress) Committee on Offshore Renewable Energy
- Focal point for the research activity of INM within the IEA Wind TCP Task 29 – Aerodynamics
- Greco, L., Testa, C., Offshore Wind Turbine Unsteady Wake Modelling by Panel Method Aerodynamics (2018) Proc. of 13th SDEWES, Palermo (Italy).
- Testa, C., Greco, L. Prediction of submarine scattered noise by the acoustic analogy (2018) Journal of Sound and Vibration, 426, pp. 186-218.
- Boorsma, K., Greco, L., Bedon, G. Rotor wake engineering models for aeroelastic applications (2018) Journal of Physics: Conference Series, 1037 (6), art. no. 062013
- Porcacchia, F., Gennaretti, M., Testa, C., Zaghi, S., Greco, L., Dubbioso, G., Muscari, R. Inclined-flow propeller hydroacoustics by the permeable Ffowcs Williams Hawkings equation (2018) 25th International Congress on Sound and Vibration 2018, ICSV 2018: Hiroshima Calling, 8, pp. 4989-4996.
- Calabretta, A., Molica Colella, M., Greco, L., Gennaretti, M. Assessment of a comprehensive aeroelastic tool for horizontal-axis wind turbine rotor analysis (2016) Wind Energy, 19 (12), pp. 2301-2319.
- Greco, L., Testa, C., Cirrincione, M., Pucci, M., Vitale, G. Effectiveness of a GNG-based MPPT and related control system for marine current turbines in unsteady operating conditions (2015) 2015 IEEE Energy Conversion Congress and Exposition, ECCE 2015, art. no. 7309801, pp. 1027-1034.
- Serafini, J., Greco, L., Gennaretti, M. Rotorcraft-pilot coupling analysis through state-space aerodynamic modelling (2015) Aeronautical Journal, 119 (1219), pp. 1105-1122.
Testa, C., Greco, L., Bernardini, G. Propeller tonal noise scattered by marine vehicles in cruise motion (2015) 22nd International Congress on Sound and Vibration, ICSV 2015.
- Greco, L., Muscari, R., Testa, C., Di Mascio, A. Marine propellers performance and flow-field prediction by a free-wake panel method (2014) Journal of Hydrodynamics, 26 (5), pp. 780-795.
- Greco, L., Testa, C., Pucci, M., Vitale, G., Cirrincione, M. Marine current turbine generator system with induction machine Growing Neural Gas (GNG) MPPT based on sensorless sea speed estimation (2014) 2014 IEEE Energy Conversion Congress and Exposition, ECCE 2014, art. no. 6953931, pp. 3901-3908.
- Leone, S., Testa, C., Greco, L., Salvatore, F. Computational analysis of self-pitching propellers performance in open water (2013) Ocean Engineering, 64, pp. 122-134.
- Testa, C., Greco, L., Salvatore, F. Computational approaches for the prediction of hull pressure fluctuations (2010) 11th International Symposium on Practical Design of Ships and Other Floating Structures, PRADS 2010, 1, pp. 102-116.
- Salvatore, F., Greco, L. Development and assessment of performance prediction tools for wind and tidal turbines (2008) RINA, Royal Institution of Naval Architects International Conference – Marine Renewable Energy – Papers, 8 p.
- Gennaretti, M., Greco, L. Whirl flutter analysis of prop-rotors using unsteady aerodynamics reduced-order models (2008) Aeronautical Journal, 112 (1131), pp. 233-242.
- Greco, L., Testa, C., Salvatore, F. Design oriented aerodynamic modelling of wind turbine performance (2007) Journal of Physics: Conference Series, 75 (1), art. no. 012011.
- Calcagno, G., Salvatore, F., Greco, L., Moroso, A., Eriksson, H. Experimental and numerical investigation of an innovative technology for marine current exploitation: The Kobold turbine (2006) Proceedings of the International Offshore and Polar Engineering Conference, 8 p.
- Gennaretti, M., Greco, L. Time-dependent coefficient reduced-order model for unsteady aerodynamics of proprotors (2005) Journal of Aircraft, 42 (1), pp. 138-147.