Bove A., De Luca F., Marsilia P.
This work presents the main facilities of the Naples Towing Tank, LEIN: the instruments and the potential of the laboratory are presented, highlighting some strategies to resolve critical points typical of the towing tank tests. As example we point the attention on three aspects, typically critical: towing point of planing vessels, the accuracy of wave spectra generation and the settings of the radii of gyration for the seakeeping models.
M. Fontana, M. Glorioso, A. Pilagatti, C. Moscoloni, G. Mattiazzo
In the racing boat design world, the most important aim is researching the best compromise between performances and safety. Nowadays, countless structural design tools exist, such as Finite Element Analysis (FEA), however every numerical model needs a controllable, repeatable, reliable experimental validation. The present work focuses on the structural design cycle adopted by Polito Sailing Team during the design and building of their own new skiff, a high-performance sailing dinghy, built mainly with natural composite material like balsa wood and flax fiber. The whole boat was completely...
Laura Poggi, Tomaso Gaggero, Marco Gaiotti, Enrico Ravina, Cesare Mario Rizzo
Adoption of Robotics and Autonomous Systems (RAS) in activities related to ship inspections has obvious potential advantages, but also shows some problems, ranging from ship-RAS interface to regulatory and legal viewpoints. The ROBINS project (ROBotics technology for INspection of Ships) is a collaborative project cofunded within the H2020 EU Research and Innovation programme call, aimed at filling the gap between current ship inspection requirements and available robotic technology. The present work aims at highlighting how human-made ship inspections can be improved using RAS, with...
Alberto Ortiz, Francisco Bonnin-Pascual, Emilio Garcia-Fidalgo, Joan Pep Company-Corcoles, Kai Yao
This paper describes a Micro-Aerial Vehicle (MAV) intended for the visual inspection of cargo holds, whose development, among others, takes place within the context of the EU-funded H2020 project ROBINS, with the purpose of making ship inspections safer and more cost-efficient. To this end, the vehicle is equipped with specific sensors that are to permit teleporting the surveyor to the areas that need inspection, while the focus of the control software is on providing enhanced functionality and autonomy for the inspection processes. All this has been accomplished in the context of the...
Giorgio Tani, Michele Viviani, Marco Ferrando
Cavitation tunnels represent one of the most important typologies of model testing facilities used in Naval Architecture. These facilities are employed to study the hydrodynamics of marine propellers, with special attention on cavitation and its side effects. These effects include: loss of propeller thrust and efficiency, erosion, inboard noise and vibration, underwater radiated noise. The latter aspect is one of the hot topics in the field of ship hydrodynamics because of the concerns related to its impact on marine life. This paper presents the general setup and test procedures used to...
Salvatore Mauro, Silvano Buogo, Junio Fabrizio Borsani
The results of the free-field calibration of an autonomous underwater noise recorder performed in an open-water test site are presented, as part of the output of the UNAC-LOW metrology research project which aimed at developing low-frequency calibration methods for hydrophones and autonomous recorders. The calibration was done for frequencies ranging from 200 Hz to 2 kHz by comparison with a reference hydrophone which was calibrated by another project partner using a closed-chamber pressure method. Calibration uncertainties were between 0.7 dB and 1.7 dB, and good agreement up to about 550...
Salvador Barrera-Figueroa, Alper Biber, Ata Can Corakci, Alexander Golick, Stephen Robinson, Gary Hayman, Justin Ablitt, Silvano Buogo, Salvatore Mauro, Fabrizio Borsani, Salvatore Curcuruto, Markus Linné, Peter Sigray, Per Davidsson
Requirements of traceability for measurements of sound pressure in the maritime environment demand that hydrophones are calibrated to frequencies down to 20 Hz. A recently completed European project entitled Underwater Acoustic Calibration Standards for Frequencies Below 1 kHz (UNACLOW), within the European Metrology Programme for Innovation and Research (EMPIR) presented a proposal for some methods of providing traceability at that frequency range. One of these methods was based on direct comparison to reference microphones in an airfilled coupler. A design of the coupler was proposed by...
F. Reseghetti, F. Pennecchi, G. Raiteri, L. Repetti
Main purpose of this work is the comparison between XBT (eXpendable BathyThermograph) temperature profiles recorded in the Tyrrhenian Sea during the SOOP (Ship Of Opportunity Programme) activity with commercial ships (since September 1999) and Argo profiles (since May 2004). In particular, analysis was focused on the Genoa-Palermo transect, historically managed by ENEA S. Teresa Research Centre. XBT temperature profiles were matched with Argo quasi-collocated in space (and quasi-simultaneous in time) profiles, in order to assess the reliability of XBT temperature measurements. Space-time...
A. Bordone, F. Pennecchi, G. Raiteri, F. Reseghetti
The widespread network of temperature/salinity profiling floats, known as Argo, has nowadays become a fundamental component of the ocean observing system. Since Argo floats usually are not recovered and should last up to five years without any re-calibration, their onboard sensors can reasonably suffer some drift and/or offset. During the years, very refined methods have been developed and implemented to post-process the Argo data, in order to correct the response of their profiling CTD (Conductivity – Temperature – Depth) sensors, in particular adjusting the salinity drift. The core of this...
Lorenzo Papa
Long term time series of annual mean sea level data collected from 1928 to 2018 in the tidal station of Genova are analized to investigate long period oscillations.