BORELLI D.

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Thin impervious layers, cloths or perforated plates are usually utilized with fibrous absorbing materials in order to avoid small particles, coming from deterioration over time or from flow abrasive effect, becoming dislodged and polluting the environment. These protective facings are to be carefully considered and analyzed, since they can...

The flute-like instruments (flute, recorders, and organ pipes) have been under physical study for more than a century; an interesting phenomenon, founded but rarely studied is the acoustic hysteresis cycle. A review regarding this acoustical effect it's carried out in this article. When the velocity of the air jet (or the pressure) is...

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Lattice Gas Automata (LGA) has emerged as a numerical technique based on the propagation and interaction of particles in a lattice. In the Computational Fluid Dynamics field, the Lattice Gas Automata is considered the precursor of the popular Lattice Boltzmann Method. Recognized for its parallelization capabilities and original mesoscopic...

The steel tongue drum (also known as hank drum) is a relatively new musical instrument (2007) in the pitched percussion family, generally made from a metal sheet or from the base of a tank. Several tongues are cut on its surface, making the instrument capable of producing different tones depending on the shape of the tongues. The sound produced...

In light of the broadening use of refrigeration in the modern industrial era and considering that conventional refrigeration fluids such as HCFCs, CFCs and HFCs are among the major causes of increased global warming, it seems necessary to implement greener and more sustainable refrigeration solutions rather than continuing to use the ordinary...

The impact of noise generated by harbour actives gained a very important role in the last years. While the evaluation of the noise impact of industrial plants and transportation is fully integrated in the activities of noise mapping in urban areas, a lack of regulation exists regarding the activities carried out in ports. The complaints of...

The Lattice Boltzmann Method (LBM) can be applied to several fluid dynamic problems in the time domain. This numerical method indirectly solves the Navier–Stokes equations in a weakly compressible limit that allows acoustic wave propagation. This work presents a systematic literature review concerning the application of the LBM in acoustics....

The use of Phase Change Materials (PCMs) in buildings, aimed at peak shavings and energy savings, has a long history and many applications. In the last decade, the use of PCMs embedded in thermal insulation layers for building envelopes become an interesting option for lightweight structures. Nevertheless, the possibility of profitably...

The issue of transmittance of thermal bridges in existing buildings has been addressed aiming to achieve correlations able to evaluate the ground-contact thermal bridges. A bi-dimensional steady state FEM model has been implemented to simulate wall-to-floor structural node and then validated in accordance with the EN ISO 10211:2017 standard....

The acoustic comfort in passenger cabins on board six passenger ships is analyzed in this paper. The overall noise inside cabins is first evaluated, then the effect of HVAC (Heating, Ventilation and Air Conditioning) is investigated and several criteria, typical from the civil field (Noise Criterion, Room Criterion, etc.), are applied and...

Innovative materials to accomplish thermal and sound insulation are constantly emerging from the industry. In this paper one of those innovative materials, mainly destinated to applications in environments such as yachts and ships, is characterized by means of a three-microphones impedance tube. In this way, acoustical and non-acoustical...

A key component in acoustic refrigerators and engines is the stack, a porous material strategically placed within a tube to harness the thermoacoustic effect. 3D printing technology for stack construction is promising due to its ability to provide accurate geometry control. One potential application is the construction of modular stacks, which...

Ports are primary importance infrastructures when considering the transportation of people and goods across the planet. Two of the biggest issues linked to harbor areas are the pollutant emissions from moored ships, as well as the huge energy demand coming from ships and other activities that take place inside of the port boundaries. To tackle...

Harbours are fundamental for the activity of many cities worldwide, moving their economy by means of trade and tourism. Travelers visit the cities around the Mediterranean coast all year long, but particularly in the summer. Large and small coastal cities have sprung up around ports. The noise produced by the numerous ships and boats that...

Harbours are fundamental for the activity of many cities worldwide, moving their economy by means of trade and tourism. Travelers visit the cities around the Mediterranean coast all year long, but particularly in the summer. Large and small coastal cities have sprung up around ports. The noise produced by the numerous ships and boats that...

Liquefied Natural Gas (LNG) is a crucial resource to reduce the environmental impact of fossil‐fueled vehicles, especially with regards to maritime transport, where LNG is increasingly used for ship bunkering. The present paper gives insights on how the installation of LNG tanks inside harbors can be capitalized to increase the energy...

Scaled models are implemented to study the radiated noise from the ships' propellers. Typically, acoustic measurements are performed inside a cavitation tunnel using those scaled models of the propeller. This work aims to present a modal acoustic characterization of the cavitation tunnel of the DITEN department of the University of Genoa in the...

: The study aims to define a methodology to evaluate the optimal insulation thickness with reference to the annual energy balance, including both heating and cooling seasons, for different climatic zones, based on three real case studies. The reduction of the heating needs due to the insulation of walls in places with cold climates is a...

Understanding the specific characteristics of onboard noise can significantly benefit human activity in different kinds of ships. Here, the perceived noise can significantly change from space to space in terms of both levels and frequency content, depending on location onboard in respect to the primary sources and on propagation paths....

The noise radiated by ship propellers can be studied by analyzing scaled models in a cavitation tunnel. However, transferring the measurements made in the enclosed space of the tunnel to the expected values in a full-scale propeller (in a free field) presents a challenge for noise measurements. An acoustic characterization of the DITEN...

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Harbour noise is an issue that in these last years is subject of a research effort financed by the European Union by means of several Programmes, such as FP7, ENPI CBC Med, LIFE and the Interreg Maritime. Within the framework of this last one, six different projects were financed, forming a cluster regarding port noise nuisance. The deep...