Ice-induced buffet on a transonic airfoil

The formation of ice on the leading edge of an aircraft wing alters the shape of the surface and consequently the flow field, affecting the pressure distribution and aerodynamic performance: increased drag, reduced maximum lift, premature stall and, in extreme cases, loss of control. This thesis investigates the impact of ice formation on a transonic airfoil using DNS and LES, focusing on how ice-induced modifications influence the buffet phenomenon and the resulting aerodynamic and structural effects.

Flow solver: STREAmS (in-house GPU code)

Screech modes in supersonic jets

Supersonic jets operating at off-design conditions produce shock-associated noise in addition to the turbulent mixing noise that dominates in subsonic and perfectly expanded jets. Shock noise has a broadband component and a tonal component known as screech, both due to the interaction between convected flow disturbances and the quasi-periodic shock-cell structure. The thesis aims to characterise and model the screech modes through a campaign of large-eddy simulations.

Flow solver: STREAmS (in-house GPU code)

Control of shock-wave/boundary-layer interaction with streamwise-travelling waves

Streamwise-travelling waves (StTW) of spanwise wall velocity are known to reduce turbulent skin friction in both low- and high-speed regimes. This thesis explores whether StTW can alleviate the detrimental effects of oblique shock-wave/turbulent boundary-layer interactions, through a campaign of direct numerical simulations.

Flow solver: STREAmS (in-house GPU code)

Micro-vortex generators for SBLI control: RANS-based shape optimisation

Shock-wave/boundary-layer interactions strongly affect the efficiency and stability of aerospace vehicles. This thesis deals with the numerical simulation of micro-ramp control of SBLI using RANS, with the goal of assessing the efficacy of micro-ramps and performing an optimisation study of the micro-vortex-generator shape.

Flow solver: Ansys Fluent or OpenFOAM

Sapienza – UT Dallas collaboration

The following theses include a visiting period at the University of Texas at Dallas, in the research group of Prof. Stefano Leonardi. Financial support is provided for the period abroad.

• Impact of offshore wind farms on ocean circulation and wildlife

• Wind-turbine modelling over complex topography

• Aeroelastic response of wind-turbine blades to turbulent wind

Flow solver: in-house code available at UT Dallas

Sapienza – ENEA collaboration

• LES of a hydrogen/air cyclonic burner operating in the MILD combustion regime at high pressure: NOx production as the operating pressure varies.

• LES of a hydrogen/ammonia/air cyclonic burner in the MILD regime: effect of the hydrogen concentration on combustion.

• DNS of a non-reacting flow under radiative heat exchange: effects of radiating species on the fluid dynamics at various pressure and temperature regimes.

Interested?

Write to matteo.bernardini@uniroma1.it with your transcript and the topics you are interested in. Theses on other subjects related to my research activities are welcome.