Iniziative e collaborazioni

Metasurfaces for hypersonic flow control

Financing provider: National Natural Science Foundation of China
Scientific Manager: Ing. Tiziano Pagliaroli
Project description
Purpose: Metasurfaces are one of the new frontier of material science and engineering, finding widespread applications in a number of fields, including acoustics and aeroacoustics. The scientific research involves a novel metasurface specifically fabricated for the hypersonic flow transition control, together with a new strategy for metasurface characterization in the ultrasonic regime.
Instead of a conventional porous layer, the metasurface here presented consists in a flat plate with a set of regularly distributed sharp slots.
We experimentally observed that such a geometry significantly reduces the wall reflection coefficient, which is known to play a fundamental role in the boundary layer transition phenomenon. Numerical simulations led us to interpret the incident wave scattering as the underlying mechanism related to the observed reflection coefficient reduction. The metasurface characterization has been carried out by comparing the conventional reflection coefficient in the Fourier domain with an innovative wavelet transform-based strategy.
Results: The main characteristic of the project metasurface are: minor manufacturing time by keeping constant the porosity, opportunity to achieve higher value of porosity, equal reflection coefficient for the same porosity, different interaction mechanism with the ultrasonic disturbances than the more common UAC.
More interesting, we have put in evidence how a multiresolution approach, like that here proposed, can be highly promising as characterization tool for further metasurfaces with a more complex and multi-scale geometry, being wavelets able to capture the multiscale behaviour of the reflected wave, overcoming the well-known limits of Fourier-based strategies of data analysis.
Other Partners: China Academy of Aerospace Aerodynamics – Beijing (China)
Total Founding: € 10.000,00
Start Date: 01.01.2018
End Date: 01.12.2018

 

convenzioni metasurfaces china

 

OSLOMET

Title: Effects of the corrosion on the steel-to-concrete interaction
Financing provider: THE OSLOMET – OSLO METROPOLITAN UNIVERSITY
Scientific Manager: Dr. Stefania Imperatore
Project description
Purpose: The scientific research involves the experimental study of the bond degradation in reinforced concrete elements damaged by corrosion. The survey will analyse different cover-to-diameter ratio are tested order to catch the splitting or the pull-out failure mode. Moreover, the different reinforcement typologies −the smooth bars, the ribbed bars, and the strands− are tested, in order to investigate the effects of the bond-slip decay in the most typical existing reinforced concrete structures.
Results: The experimental campaign will analyse aspects not completely covered by the scientific literature, providing a deep understanding of the decay in the bond-slip relationship.
Other Partners: THE OSLOMET – OSLO METROPOLITAN UNIVERSITY
Total Founding: € 4.500,00
Start Date: 05.03.2019
End Date: 05.04.2020

1st Research Agreement

convenzioni OSLOMET 1

Title: Effect of the corrosion on structural integrity of prestressed reinforced concrete beams
Financing provider: THE OSLOMET – OSLO METROPOLITAN UNIVERSITY
Scientific Manager: Dr.
Stefania Imperatore
Project description
Purpose: TThe scientific research involves the analysis of the structural integrity of prestressed reinforced beams damaged by corrosion. The research will consist in the artificial corrosion process of three prestressed beams with the same corrosion level (20%) but different extension of damage. As reference, another beam will be tested without the superposition of the artificial corrosion process. The experimental survey will allow the development of numerical and analytical models able to permit a reliable simulation of the behaviour of existing structures. Results: It is expected that with the increasing of the corrosion extension, the structural capacity proportionally will decrease.
Other Partners: THE OSLOMET – OSLO METROPOLITAN UNIVERSITY
Total Founding: € 8.000,00
Start Date: 20.03.2019
End Date:  20.04.2020

2nd Research Agreement

convenzioni OSLOMET 1