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1

Impact of hydrodynamics on ship handling characteristics in training simulators

Kobyliński L.

Zeszyty Naukowe Akademii Morskiej w Szczecinie

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2016

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nr 45 (117)

9--16

EN

Currently, ship operators (ship masters and pilots) are trained on ship simulators, either Full Mission Bridge (FMB) simulators, or Manned Model (MM) simulators. Both types of simulator increase an operator’s skill in manoeuvring a ship, and both incorporate the impact of hydrodynamic forces on the handling characteristics of a simulated ship. However, all forces affecting manoeuvring are the result of flow patterns that build up around the hull. These flow patterns may have extremely complex effects on many practical manoeuvres. Recent advances in hydrodynamic theory allow the impact of hydrodynamic forces on manoeuvrability to be simulated quite accurately so long as the simulated ship is moving straight ahead or performing standard manoeuvres. These advances also allow the simulation of such external influences as bank effects, shallow water effects, and canal effects, as well as the effect of the passage of other ships in the immediate vicinity. With a measure of simplification, these effects can be incorporated in FMB simulators. They can also be simulated by MM simulators provided both the models and training areas are properly prepared. As they are now, training simulators do not contribute to a trainee’s understanding of the way in which flow patterns develop or of the forces they create. This article discusses this deficiency and proposes a solution for it. Several examples of specific manoeuvring scenarios are used to illustrate the solution.

2

Bank effect and operation of inland waterways vessels

Kobyliński L.

Zeszyty Naukowe / Akademia Morska w Szczecinie

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2014

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nr 37 (109)

50--55

EN

Inland waterways vessels operate in waters of restricted depth and restricted width with cross-section of the waterway of different profile. These conditions affect hydrodynamic forces acting on the vessel and in consequence they affect their operation. There are several hydrodynamic effects present in inland waterways. Restricted depth and cross-section of the canal or river affects resistance of the vessel and hydrodynamic characteristics of the propeller and in consequence propulsive efficiency. Another effect is caused by modification of pressure distribution around vessel body resulting in change of draft, so called squat. Finally in narrow fairway lateral forces on the vessel are created and in case of non-symmetrical position of the vessel, those forces are also non-symmetric and causing that the vessel is pushed to one side. This affects safe handling of the vessel and requires understanding and skill of operator. This problem is discussed in the paper.

3

Capabilities of Ship Handling Simulators to Simulate Shallow Water, Bank and Canal Effects

Kobyliński L.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2011

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Vol. 5, no. 2

247--252

EN

Safe operation of ships in restricted areas, in particular in canals and waterways of restricted width and depth, often with presence of current. depends on operator skill. One way to influence operator skill and hence to increase safety against collisions and groundings is proper training of operators in realistic envi-ronment. Training could be accomplished on board ships, which takes, however, long time but also on simula-tors. There are two types of simulators: full mission bridge simulators (FMBS) working in real time and phys-ical simulators using large manned models in purposeful prepared training areas (MMS). Capabilities of both type simulators are discussed in detail. Capability of FMBS depends on computer codes governing them. Few examples of capability of FMBS to reproduce correctly ship handling situations are shown. There are few MMS in the world, one of which is Ilawa Ship Handling Research and Training Centre. In the centre models of several types of ships are available and training areas are developed representing different naviga-tional situations. The main purpose of the training exercises is to show the trainees how to handle the ship in many close proximity situations, in the presence of current, in very restricted water areas etc.

4

Steady State Ship Attitude during Manoeuvres in a Bank Vicinity

Artyszuk J.

Zeszyty Naukowe / Akademia Morska w Szczecinie

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2004

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nr 2 (74)

45-57

EN

The existing regression models on the bank (wall) effect are compared to one another both dynamically (force level) and kinematically (counteracting helm and hull drift attitude during a steady-state passage along a bank). A small chemical tanker of known hull and rudder hydrodynamics is used as an example of computations. A lot of essential qualitative and quantitative discrepancies have been found, which might claim the regression models of little use in an adequate bank effect simulation. Further research is required in this field.

PL

Przeprowadzono symulację efektu brzegowego w kanale dla małego chemikaliowca, wykorzystując dostępne modele regresyjne tego zjawiska. Główny nacisk położono na wielkość dryfu i wychylenie steru potrzebne do zrównoważenia efektu brzegowego podczas ustalonego ruchu jednostki poza osią kanału. Stwierdzono zasadnicze różnice między poszczególnymi modelami, co uniemożliwia uzyskanie prawdziwego ilościowego obrazu zjawiska. Konieczne są dalsze prace nad modelowaniem efektu brzegowego.