Reference person
Luigi de Luca - Professor of Fluid Dynamics (ING-IND/06)
ERC sectors
PE8_1 Aerospace engineering
PE8_5
Fluid mechanics, hydraulic-, turbo-, and piston engines
Group components
Matteo Chiatto - RTDa
Alessandro Della Pia - PhD student (DII)
Antonio Colanera - PhD student (DII)
Acquaviva Maria Rosaria - PhD student (DII)
External components
Onofrio Semeraro - Researcher (Université Paris-Saclay, France)
Andrea Palumbo - Post-doc
Activity outlines

The Modal analysis, Stability and Numerical Simulation for Flow Control group is active in both theoretical and computational research fields of hydrodynamic stability and control as well as numerical simulation in thermo-fluid-dynamics.

The group has a consolidated background in theory and methods of hydrodynamic stability as well as in modern modal decomposition methods of flow fields (POD, SPOD, DMD). The focus is mainly on linear stability analysis and the methods span from classical eigenvalues analysis to more modern non modal theories. The applications developed over the past years have been made in the analysis of shear and capillary instabilities of two-phase flows, such as the stability of a gravitational liquid jet (sheet or curtain) subjected to surface tension, to be employed for instance in the technology of coating deposition. Recent research activity has focused on the experimental characterization of another kind of liquid jets, namely the air-water two-phase flow behind a plane splitter plate, for the analysis of the related wake-mixing layer flow in the framework of the atomization and spray in combustors. Another research interest is related to the analysis and the development of micro-devices devoted to flow control (and also to heat transfer cooling), the so called piezo-driven and plasma synthetic jet actuators. The group developed a lumped-element physical model to predict the frequency response of both kinds of devices. The model was validated through experimental tests carried out on home-made devices having different mechanical and geometrical characteristics. More recently, the spark-jet plasma actuator device has been addressed, from both the theoretical modeling and the experimental viewpoints. Such flow control actuators can be used to modify (delay) the laminar-to-turbulent transition, to prevent or induce separation, and to enhance aerodynamic performances of airfoils (e.g., high lift). Applications have been carried out to control the flow over a backward facing ramp flow, on a morphing flap and on a vertical tail of an aircraft.

The objective of the research in modal decomposition methods is to characterize the spatial and temporal properties of flow fields, extracting their basic features in terms of both spatial structures and dominant frequencies; once the main modes have been identified, a low rank reconstruction of the field can be performed either in frequency or in temporal domain. Within this framework, the flow control devices can be analyzed by both direct numerical simulation and data-driven modal decomposition techniques, with the formulation of Reduced Order Models (ROM) which can be helpful both to gain further insights on the features of the flow field and to carry out fast predictions regarding the effectiveness of the control strategies. These techniques have been applied to: two-phase flows like liquid jets (of relatively low and high velocity); backward facing ramp and curved cylinder; piezo-driven and plasma synthetic jets to be employed for flow control.

The numerical simulation activity is conducted within three main research fields. The first one is relative to the applications of Volume of Fluid (VOF) techniques to complex two-fluid systems. Examples of recent applications are the study of liquid jets (both gravitational and behind a splitter plate of fuel injectors systems). The second research topic, related to the numerical simulation activity, is relative to the flow through small orifices (holes) of particular shaped geometry of thin plates used in the film cooling technology of aeronautic combustors. Finally, the third topic regards the simulation of the flow field produced by synthetic jet actuators (piezo-driven plasma devices), focusing both on the flow produced within the cavity and the one at the orifice exit section.

Collaborations
Prof. Francesco Grasso and Markus Hultmark, University of Princeton
Prof. Marios Kotsonis, Delft University of Technology, Delft, The Netherlands
Prof. Jean-Christophe Robinet, DynFluid Laboratory, Arts et Métiers ParisTech, Paris
Prof. Jessica Shang, University of Rochester AVIO GE, Pomigliano CIRA, Capua
Recent visiting research activity

Alessandro Della Pia, 11 months from March 2021 to January 2022, at University of Technology of Delft, under the supervision of Prof. Marios Kotsonis.

Paper produced:

Alessandro Della Pia, Theodoros Michelis, Matteo Chiatto, Marios Kotsonis and Luigi de Luca, Experimental analysis of the wake-mixing layer flow behind a plane splitter plate, to be submitted to Journal of Fluid Mechanics, 2022

Recent Research Projects

Distretto Aerospaziale Campano DAC, progetto regionale MISTRAL “Thermal control of a small satellite”, Responsabile del WP 1B-ABBB Thermal Analysis Support, 2015-2020 (46k Euro)

Progetto Europeo Clean Sky Air Green, JTI-CS2 CPW1-REG-01-02 “Plasma Synthetic Jet Actuators for High Lift Devices” (responsabile di unità locale), 2015-oggi (120k Euro)

C.I.R.A. nell’ambito del contratto SHAFT (Synthetic Jet Actuators for flow control) project (35k Euro) 2017-2020

AVIO AERO, nell’ambito del contratto “CFD Analysis to estimate the sensitivity of the pressure drop, measured through a shaped hole, by a proper pneumatic gauge, as the geometrical parameters are changed”, (35k + 35kEuro), 2021-oggi

Bando per Progetti di Ricerca di RTDa del Dipartimento, “plasma Synthetic jet actuators to Control AircRaft Yaw moment (SCARY)". 15kEuro, 2021- 2022.

Recent Publications

Andrea Palumbo, Onofrio Semeraro, Jean-Christophe Robinet, Luigi de Luca
Boundary layer transition induced by low-speed synthetic jets
(2022) to appear in Physics of Fluids

Colanera, A., Della Pia, A., Chiatto, M.
Data-driven global stability of vertical planar liquid jets by dynamic mode decomposition on random perturbations
(2022) Physics of Fluids, 34 (12) 122101
DOI: 10.1063/5.0123550

Chiatto, M., Della Pia, A.
Natural frequency discontinuity of vertical liquid sheet flows at transcritical threshold
(2022) Journal of Fluid Mechanics, 945, A32
DOI: 10.1017/jfm.2022.578

Della Pia, A., Colanera, A., Chiatto, M.
Surface tension-induced instability in spatially developing subcritical liquid curtains
(2022) Physics of Fluids, 34 (4), 042122
DOI: 10.1063/5.0087264

Palumbo, A., de Luca, L.
Experimental and CFD Characterization of a Double-Orifice Synthetic Jet Actuator for Flow Control
(2021) Actuators, 10 (12), art. no. 326
DOI: 10.3390/act10120326

Ceglia, G., Chiatto, M., Greco, C.S., De Gregorio, F., Cardone, G., de Luca, L.
Active control of separated flow over 2D back-facing ramp by an array of finite-span slotted synthetic jets
(2021) Experimental Thermal and Fluid Science, 129, art. no. 110475
DOI: 10.1016/j.expthermflusci.2021.110475

Della Pia, A., Colanera, A., Chiatto, M., De Luca, L.
Energy insights into the unsteady dynamics of a viscous gravitational liquid sheet
(2021) Physics of Fluids, 33 (9), art. no. 092118
DOI: 10.1063/5.0065590

Colanera, A., Della Pia, A., Chiatto, M., de Luca, L., Grasso, F.
Modal decomposition analysis of unsteady viscous liquid sheet flows
(2021) Physics of Fluids, 33 (9), art. no. 092117
DOI: 10.1063/5.0065683

Chiatto, M., De Luca, L., Grasso, F.
Modal analysis of actively controlled flow past a backward facing ramp
(2021) Physical Review Fluids, 6 (6), art. no. 064608
DOI: 10.1103/PhysRevFluids.6.064608

Chiatto, M., Shang, J.K., De Luca, L., Grasso, F.
Insights into low Reynolds flow past finite curved cylinders
(2021) Physics of Fluids, 33 (3), art. no. 035150
DOI: 10.1063/5.0043222

Della Pia, A., Chiatto, M., De Luca, L.
Receptivity to forcing disturbances in subcritical liquid sheet flows
(2021) Physics of Fluids, 33 (3), art. no. 032113
DOI: 10.1063/5.0044322

Ceglia, G., Invigorito, M., Chiatto, M., Greco, C.S., Cardone, G., de Luca, L.
Flow characterization of an array of finite-span synthetic jets in quiescent ambient
(2020) Experimental Thermal and Fluid Science, 119, art. no. 110208
DOI:10.1016%2fj.expthermflusci.2020.110208

Della Pia, A., Chiatto, M., De Luca, L.
Global eigenmodes of thin liquid sheets by means of Volume-of-Fluid simulations
(2020) Physics of Fluids, 32 (8), art. no. 20559
DOI: 10.1063/5.0020559

Palumbo, A., Chiatto, M., de Luca, L.
The role of the critical layer in the channel flow transition revisited
(2019) Meccanica, 54 (14), pp. 2169-2182.
DOI: 10.1007/s11012-019-01079-z

Chiatto, M., Palumbo, A., de Luca, L.
Design approach to predict synthetic jet formation and resonance amplifications
(2019) Experimental Thermal and Fluid Science, 107, pp. 79-87.
DOI: 10.1016/j.expthermflusci.2019.05.013