Towing dynamics of Ship in Harbour Areas (TOWING)

Duration: 01.04.2010-31.03.2013 (36 months)

Coordination: Instituto Superior Técnico

Funding Entity: Portuguese Foundation for Science and Technology

In spite of some progress in the ship control devices observed during several last decades (lateral bow thrusters as typical equipment, increasing application of the azimuthal main thrusters), most sea-going vessels and naval ships require tug assistance when manoeuvring in harbours especially under worsened environmental conditions, Crenshaw (1965), Hensen (2006). Successful use of tugs in towing and pushing mode is mainly based on experience and good ship handling practice. However, possibility of adequate simulation of the tug assisted manoeuvring motion in real and scaled time can be very helpful for tug operators and harbour services in the decision making process: success and efficiency of a berthing operation depends on how adequate is the number of applied tugs, how they are positioned and which strategy are they supposed to follow. These questions can be relatively easily answered by means of a rather advanced desktop simulator (bridge simulators can also be helpful in solving such problems but they are very expensive and mainly aimed at training skippers and operators). Besides that, sometimes tug operations bring accidents. One such accident when a tug was hit by the tanker’s propeller was described by Eda et al. (2006) who used model tests and simulations for reproducing the situation. Possibility of simulation of harbour entrance and berthing operations can also be very helpful in planning and designing new harbour areas. The present project has, as its main objective, development of a specialized desktop towing simulator with emphasis to creation of an advanced core mathematical model. One of the main ideas behind this task is representation of the towed ship, of any of the assisting tugs, and of any towline as linked objects inside the computer code. The object-oriented core manoeuvring mathematical model has already been created by the proponents (Sutulo and Guedes Soares 2005). In its present state, it permits creation and simultaneous simulation of any number of ships but it must be enhanced with referencing capabilities.

Project Team

Associated Publications