1,721,058 research outputs found
On the Calculation of the Forces Developed by escort Tugs
No full textAuthorities and harbour operators demand tugs to assist ever-larger ship in more severe weather conditions in confined waters. The escort of such ships is carried out by specially designed tugs connected to the assisted ship by a towline in order to control course and speed of the assisted ship when comes to sail in potentially dangerous situations, and so the risk of grounding and collision is strongly reduced. In order to achieve the "escort tug" service notation it is necessary to predict the maximum steering forces applied on the assisted ship at different speeds. The paper deals with a method for the prediction of the escort capabilities of a tug through the quasi-steady solution of the dynamic equilibrium
Interventi di refitting per un superyacht con sovrastruttura ibrida in materiale composito e acciaio
No full textIn questo lavoro viene presentato un piano di fattibilit`a per la conversione di un piccolo traghetto d’epoca in superyacht, impostando sullo scafo originale di acciaio nuove sovrastrutture. In particolare, per queste ultime si `e fatto ricorso al concetto di struttura ibrida, intesa come costruzione realizzata con pannelli in sandwich di materiale composito sostenuti da telai in acciaio. Lo studio ha evidenziato che la soluzione innovativa proposta
offre al progettista notevoli convenienze sia dal punto di vista tecnico-realizzativo quanto da quello estetico-distributivo. Il refitting dell’unit`a, oltre alla radicale trasformazione dei volumi esterni, ha portato ad una risistemazione delle zone abitative interne e dei relativi percorsi. Parallelamente, anche l’impiantistica di bordo `e stata ripensata in aderenza alla nuova vocazione diportistica
La gestione dell'energia in un catamarano da diporto: una proposta per l'integrazione con fonti rinnovabili
No full textL’esercizio del diporto nautico è intrinsecamente connesso con il rispetto dell’ambiente stesso in cui viene a svolgersi. La progettazione e la gestione di una imbarcazione da diporto non potrà quindi prescindere da scelte e comportamenti responsabili nei confronti della tutela ambientale. La moderna nautica da diporto, per poter rispondere efficacemente a queste tematiche e allo stesso tempo essere sempre più competitiva sul mercato, dovrà essere vista come laboratorio in cui sperimentare quelle tecnologie, oramai sufficientemente mature, in grado di far fronte alle esigenze di ecosostenibilità del sistema.
Con queste convinzioni è stato elaborato il progetto di un catamarano motor-sailer in cui è stata prevista l’installazione di moduli fotovoltaici capaci di integrare con continuità il fabbisogno energetico di bordo. Ne è scaturita una soluzione interessante che vede la tecnologia del fotovoltaico ben affiancarsi alle tecnologie tradizionali impiegate per la propulsione e la generazione di energia
Hybrid Electric Propulsion for an Eco-Friendly Inland Waterway Passenger Catamaran
No full textThe design of a passenger catamaran conceived for tourist lake navigation is presented. The operational area considered is a small lake in northern Italy with a mild climate, and consequently with a quite moderate environmental demand acting on the vessel. Moreover, the peculiar service suggests the adoption of eco-friendly solutions to provide power for both propulsion and on-board use. Specifically, a series hybrid power system has been set up: the electric energy is generated by different sources, and stored in batteries; two electric motors drive each propeller shaft directly. Even if such a system calls for higher costs of purchase and maintenance, it offers a very appreciable low environmental impact in terms of fuel consumption, noise and gas emissions.
The paper presents the design of a catamaran complying with the European Directive 2006/87/EC, which establishes harmonized conditions for issuing technical certificates for inland waterway vessels throughout the European Community's inland waterway network.
General arrangement, midship section, power balance and power management system distribution diagram are reported
Influence of the "Safe Return to Port" standards on the integrated design and arrangements of small passenger ships
No full textOn the Design of Ice-Strengthened Superyachts
No full textThe paper deals with the design of ships strengthened for navigation in icy waters. The attention is focused, in particular, on the expedition yachts: innovative luxury vessels conceived
for a service also in harsh climate regions. For such a special yacht the design must face the problems related to the navigation in brash ice channels, and for this reason the vessel must comply with an ice class regulation.
The ice class rules of the Finnish and Swedish Maritime Administrations can be considered
as the main reference in this field; indeed these regulations have been adopted by most of the
IACS members since 1985.
The design philosophy behind the ice class rules is analysed in relation to its main features, which are essentially based on both operative and safety aspects. A sensitivity analysis is
performed on the parameters affecting the structural scantling and the propulsion power requirements.
The ice class concepts have been applied for an expedition yacht 35 m long. Feasible structural solutions for the ice-strengthened hull are shown along with the verification of the powering needed for a safe navigation in ice
Performance Prediction of a Slender Half-Displacement Passenger Craft for Inland Navigation
No full textThe design of a small passenger craft for Venice is presented. The paper deals with hy-drodynamic aspects mainly concerning resistance prediction in shallow water for sub-critical, critical and supercritical regimes. Usually, open Literature provides methods for the subcritical regime only. Here, a procedure for the estimation of added resistance in subcritical, critical and supercritical regimes is presented within the slender body ap-proximation. The developed procedure is suitable to be used in the early design stage to predict a preliminary speed-power curve. A test case based on the designed half-displacement craft is thoroughly exposed
- …
