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Avallone, F. (author), Correale, G. (author)
An experimental investigation was conducted on the effective efficiency of a nanosecond Dielectric Barrier Discharge (ns-DBD) plasma actuator. Back-current shunt technique and infrared thermography measurements were carried out at the same time on an upside-down flat plate in a quiescent environment. The only investigated parameter was thickness...
conference paper 2015
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Avallone, F. (author), Ragni, D. (author), Schrijer, F.F.J. (author), Scarano, F. (author), Cardone, G. (author)
In this study, the mean flow organization in the symmetry plane of the recirculation region ahead of a cylindrical roughness element immersed in an incoming laminar boundary layer at Mach number equal to 6.5 is investigated. The flow topology is inspected with planar particle image velocimetry (PIV), InfraRed (IR) Thermography and Schlieren flow...
conference paper 2015
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Crispo, C.M. (author), Greco, C.S. (author), Avallone, F. (author), Cardone, G. (author)
Abstract.
conference paper 2015
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Avallone, S. (author), Kuipers, F.A. (author), Ventre, G. (author), Van Mieghem, P. (author)
conference paper 2005
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Kleiberg, T. (author), Fu, B. (author), Kuipers, F.A. (author), Avallone, S. (author), Quoitin, B. (author), Van Mieghem, P. (author)
conference paper 2008
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Avallone, S. (author), Kuipers, F.A. (author), Ventre, G. (author), Van Mieghem, P. (author)
The problem of finding multi-constrained paths has been addressed by several QoS routing algorithms. While they generally satisfy the application requirements, they often do not consider the perspective of service providers. Service providers aim at maximizing the throughput and the number of accepted requests. These goals have been addressed by...
conference paper 2005
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Avallone, S. (author), Kuipers, F. (author), Ventre, G. (author), Van Mieghem, P. (author)
conference paper 2006
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Fiscaletti, D. (author), Luesutthiviboon, S. (author), Avallone, F. (author), Casalino, D. (author)
Streamwise fences for the reduction of the trailing-edge noise are experimentally investigated on a NACA633018 airfoil. Interchangeable trailing-edge inserts with streamwise fences of different spacing and height are tested in an anechoic wind tunnel. Far-field trailing-edge noise was measured by an array of microphone and the airfoil drag was...
conference paper 2022
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Avallone, F. (author), Manjunath, P. (author), Ragni, D. (author), Casalino, D. (author)
A lattice-Boltzmann Very Large Eddy simulation of a multi-orifice acoustic liner, grazed by a turbulent flow at Mach number equal to 0:3 and a planar acoustic wave with amplitude equal to 130 dB and frequency equal to 1800 Hz, is carried out. The geometry of the liner replicates the experiments carried out in the Grazing Flow Impedance Tube ...
conference paper 2019
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Teruna, C. (author), Rego, Leandro (author), Casalino, D. (author), Ragni, D. (author), Avallone, F. (author)
High-fidelity numerical simulations have been performed to investigate the noise reduction capability of porous leading-edge treatments for mitigating rotor-stator interaction noise in a full-scale aircraft model. The aircraft model consists of the NASA High-Lift Common Research Model (HL-CRM) airframe combined with an up-scaled Source...
conference paper 2022
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Zamponi, R. (author), Avallone, F. (author), Ragni, D. (author), van der Zwaag, S. (author)
Coating a circular cylinder with porous materials constitutes an effective passive strategy for reducing the flow-induced noise linked to the vortex shedding. Despite the number of investigations in the last decade, the noise-mitigation mechanisms associated with this technique remain unclear. The present research aims to clarify the role played...
conference paper 2022
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Vergés i Plaza, G. (author), Fischer, Andreas (author), Lylloff, Oliver (author), Bak, Christian (author), Olsen, Anders S. (author), Luesutthiviboon, S. (author), Lima Pereira, L.T. (author), Ragni, D. (author), Avallone, F. (author)
An experimental aero-acoustic characterisation of the NACA 63 <sub>3</sub>-018 airfoil is presented in this study, featuring trailing-edge noise emissions with and without serrations. Measurements have been carried out for a chord-based Reynolds number range between 0.18 × 10 <sup>6</sup> and 4.8 × 10 <sup>6</sup> . Two airfoil models with...
conference paper 2022
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Arcondoulis, Elias J. G. (author), Liu, Yu (author), Yang, Yannian (author), Ragni, D. (author), Rubio Carpio, A. (author), Avallone, F. (author)
The application of a porous coating to a cylinder can significantly reduce the vortex shedding tone when placed in a uniform flow. The mechanism of how this porous media attenuates vortex shedding has been studied more in recent years yet it is still not fully understood. Typical porous materials within a certain range of porosity and airflow...
conference paper 2022
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Bennett, Gareth J. (author), Lai, Jiang (author), O'Brien, Gordon C. (author), Ragni, D. (author), Avallone, F. (author), Rubio Carpio, A. (author), Pott-Pollenske, Michael (author)
This paper examines the use of both flow control and passive low noise technologies to reduce the aerodynamic noise radiated from a modified LAGOON landing gear, as tested in the EU funded H2020 collaborative research project: INVENTOR, InnoVative dEsign of iNstalled airframe componenTs for aircraft nOise Reduction. At approach to landing,...
conference paper 2022
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Meirelles Pereira, L. (author), Bonomo, Lucas A. (author), da Silva, Andrey R. (author), Cordioli, Júlio A. (author), Avallone, F. (author)
Scaled-resolved numerical simulations using the lattice-Boltzmann Very Large Eddy Simulation method are performed to compute the acoustic impedance of a realistic multi-cavity single degree of freedom liner grazed by a turbulent boundary layer. Numerical results are assessed against experimental impedance measurements carried out in grazing flow...
conference paper 2022
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Yunus, F. (author), Casalino, D. (author), Avallone, F. (author), Ragni, D. (author)
This work presents a novel noise propagation approach based on the Gaussian Beam Tracing (GBT) method that accounts for complex source directivity, weather conditions, and irregular ground topology for the evaluation of the noise footprint. The approach takes a precomputed noise sphere as input and propagates the acoustic pressure...
conference paper 2022
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Grande, E. (author), Ragni, D. (author), Avallone, F. (author), Casalino, D. (author)
This paper explains the presence and relevance of noise caused by a laminar separation bubble (LSB) on a propeller operating at low-Reynolds number. Microphone measurements of a propeller with both clean and forced boundary layer transition blades are carried out in an anechoic wind tunnel by varying the propeller advance ratio J from 0 to 0...
conference paper 2022
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Rego, Leandro (author), Zamponi, R. (author), Ragni, D. (author), Avallone, F. (author), Casalino, D. (author), Cruellas Bordes, M. (author)
An experimental investigation on jet-installation noise reduction with permeable flaps on an aircraft half-model is performed, focusing on the effects on the noise levels as well as on the aerodynamic properties of the model (lift and drag forces). A nozzle with an exit diameter = 113 mm is included for generating a single-stream jet flow in...
conference paper 2022
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Boatto, U. (author), Bonnet, Jean-Paul (author), Avallone, F. (author), Ragni, D. (author)
The design of efficient rotor blades is affected by the accuracy of aerodynamic prediction methods for load distributions and power computations. Research showed that the accuracy of BEMT-based industrial codes decreases at high inflow-speed under uniform aligned steady conditions. The identified reasons are inaccuracies in the semi-empirical...
conference paper 2023
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Arce Leon, C.A. (author), Merino Martinez, R. (author), Ragni, D. (author), Pröbsting, S. (author), Avallone, F. (author), Singh, A. (author), Madsen, Jesper (author)
Trailing edge serrations have been proven to work as a passive noise reduction device. Nevertheless, they have also previously been found to increase noise in a particular frequency range, argued in earlier research to be due to the misalignment of the serrations with the direction of the flow in the wake. It emerges as a high-frequency noise...
conference paper 2017
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