A ship model basin may be defined as one of two separate yet related entities, namely:

• a physical basin or tank used to carry out hydrodynamic tests with ship models, for the purpose of designing a new (full sized) ship, or refining the design of a ship to improve the ship's performance at sea;

• the organization (often a company) that owns and operates such a facility.

In the second meaning, the company or authority is an engineering firm that acts as a contractor to the relevant shipyards, and provides hydrodynamic model tests and numerical calculations to support the design and development of ships and offshore structures. A dock is an area of water between two piers or alongside a pier, forming a chamber used for building or repairing one ship. ... Hydrodynamics is fluid dynamics applied to liquids, such as water, alcohol, oil, and blood. ... Model of a 19th-century vessel in the Bishop Museum, Hawaii Ship models (or model ships) are scale representations of sea-going vessels. ... Small shipyard in Klaksvík (Faroe Islands), reparing fishing vessels Fish ladder and shipyard in Grave, the Netherlands Construction hall of Schichau Seebeck Shipyard, Bremerhaven Gdynia Shipyard Shipyards and dockyards are places which repair and build ships. ...

The hydrodynamic test facilities present at a model basin site include at least

A model being tested in the Towing Tank of Newcastle University.

• A towing tank: This is a basin, several meters wide and hundreds of meters long, equipped with a towing carriage that runs on two rails on either side. The towing carriage can either tow the model or follow the self-propelled model, and is equipped with computers and devices to register or control, respectively, variables such as speed, propeller thrust and torque, rudder angle etc. The towing tank serves for resistance and propulsion tests with towed and self-propelled ship models to determine how much power the engine will have to provide to achieve the speed laid down in the contract between shipyard and ship owner. The towing tank also serves to determine the maneuvering behavior in model scale. For this, the self-propelled model is exposed to a series of zig-zag maneuvers at different rudder angle amplitudes. Post-processing of the test data by means of system identification results in a numerical model to simulate any other maneuver like Dieudonné spiral test or turning circles. Additionally, a towing tank can be equipped with a PMM (planar motion mechanism) or a CPMC (computerized planar motion carriage) to measure the hydrodynamic forces and moments on ships or submerged objects under the influence of oblique inflow and enforced motions. The towing tank can also be equipped with a wave generator to carry out seakeeping tests, either by simulating natural (irregular) waves or by exposing the model to a wave packet that yields a set of statistics known as response amplitude operators (acronym RAO), that determine the ship's likely real-life sea-going behavior when operating in seas with varying wave amplitudes and frequencies (these parameters being known as sea states). Modern seakeeping test facilities can determine these RAO statistics, with the aid of appropriate computer hardware and software, in a single test.

Cavitation tunnel of the Versuchsanstalt für Wasserbau und Schiffbau in Berlin

Cavitating propeller in a water tunnel experiment at the David Taylor Model Basin

• A cavitation tunnel to investigate propellers. This is a vertical water circuit with large diameter pipes. At the top, it carries the measuring facilities. A parallel inflow is established. With or without a ship model, the propeller, attached to a dynamometer, is brought into the inflow, and its thrust and torque is measured at different ratios of propeller speed (number of revolutions) to inflow velocity. A stroboscope synchronized with the propeller speed serves to visualize cavitation as if the cavitation bubble would not move. By this, one can observe if the propeller would be damaged by cavitation. To ensure similarity to the full-scale propeller, the pressure is lowered, and the gas content of the water is controlled.

• Workshops: Ship model basins manufacture their ship models from wood or parrafine with a computerized milling machine. Some of them also manufacture their model propellers. Equipping the ship models with all drives and gauges and manufacturing equipment for non-standard model tests are the main tasks of the workshops.

Some ship model basins have further facilities, for example: Image File history File linksMetadata Size of this preview: 800 × 600 pixelsFull resolution (1280 × 960 pixel, file size: 242 KB, MIME type: image/jpeg) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File linksMetadata Size of this preview: 800 × 600 pixelsFull resolution (1280 × 960 pixel, file size: 242 KB, MIME type: image/jpeg) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Newcastle University is a British university located in Newcastle upon Tyne in the north of England. ... System identification is a general term to describe mathematical tools and algorithms that build dynamical models from measured data. ... In the field of ship design and design of other floating structures, a Response Amplitude Operator is an engineering statistic, or set of such statistics, that are used to determine the likely behaviour of a ship when operating at sea. ... Sea state refers to the height, period, and character of waves on the surface of a large body of water. ... Image File history File linksMetadata Download high resolution version (2304x1728, 1514 KB) Beschreibung / Description Berlin-Mitte, Tiergarten, Müller-Breslau-Straße, Schleuseninsel – Kavitationstunnel der Versuchsanstalt für Wasserbau und Schiffbau / cavitation tunnel (hydrodynamic test facility) Quelle / Source selbst fotografiert / taken by myself Datum der Aufnahme / Time of creation 2005... Image File history File linksMetadata Download high resolution version (2304x1728, 1514 KB) Beschreibung / Description Berlin-Mitte, Tiergarten, Müller-Breslau-Straße, Schleuseninsel – Kavitationstunnel der Versuchsanstalt für Wasserbau und Schiffbau / cavitation tunnel (hydrodynamic test facility) Quelle / Source selbst fotografiert / taken by myself Datum der Aufnahme / Time of creation 2005... Image File history File links Cavitating-prop. ... Image File history File links Cavitating-prop. ... Cavitation tunnel of the Versuchsanstalt für Wasserbau und Schiffbau in Berlin // Definition A water tunnel is an experimental facility used for testing the hydrodynamic behavior of submerged bodies in flowing water. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... A dynamometer, or dyno for short, is a machine used to measure torque and rotational speed (rpm) from which power produced by an engine, motor or other rotating prime mover can be calculated. ... A stroboscope , also known as a strobe, is an instrument used to make a cyclically moving object appear to be slow-moving or stationary. ... Endmills for a milling machine. ...

• A maneuvering and seakeeping basin. This is a test facility that is wide enough to investigate arbitrary angles between waves and the ship model, and to perform maneuvers like turning circles, for which the towing tank is too narrow. However, some important maneuvers like the spiral test still require even more space and still have to be simulated numerically after system identification.

• An Ice Tank: To develop ice breaking vessels, this tank fulfills similar purposes as the towing tank does for open water vessels. Resistance and required engine power as well as maneuvering behavior are determined depending on the ice thickness. Also ice forces on offshore structures can be determined. Ice layers are frozen with a special procedure to scale down the ice crystals to model scale. Also tests in brash ice are performed.

Additionally, these companies or authorities have CFD software and experience to simulate the complicated flow around ships and their rudders and propellers numerically. Today's state of the art does not yet allow software to replace model tests in their entirety by CFD calculations. One reason, but not the only one, is that elementization is still expensive. Also the lines design of some of the ships is carried out by the specialists of the ship model basin, either from the beginning or by optimizing the initial design obtained from the shipyard. The same applies to the design of propellers. An Ice Tank is a ship model basin whose purpose is to provide a physical modeling evironment for the interaction of ship, structures, or sea floor with both ice and water. ... Icebreaker Polarstern Track of research vessel Polarstern while breaking ice in the Southern Ocean An icebreaker is a special purpose ship or boat designed to move and navigate through ice-covered waters. ... A computer simulation of high velocity air flow around the Space Shuttle during re-entry. ...

The ship model basins worldwide are organized in the ITTC (International Towing Tank Conference) to standardize their model test procedures.

Some of the most significant ship model basins are the David Taylor Model Basin in the United States, SSPA [1] in Gothenburg, Sweden, the MARIN [2] in Wageningen, the Netherlands, the INSEAN in Rome, Italy, the HSVA[3] in Hamburg, Germany, the "Bassin d'essai des carènes" in Val de Reuil [4], France and CEHIPAR [5]in Madrid, Spain, CTO S.A. [6] in Gdansk, Poland The David Taylor Model Basin is one of the largest ship model basins — test facilities for the development of ship design — in the world. ... Nickname: Motto: SPQR: Senatus Populusque Romanus Location of the city of Rome (yellow) within the Province of Rome (red) and region of Lazio (grey) Coordinates: Region Lazio Province Province of Rome Founded 21 April 753 BC Government  - Mayor Walter Veltroni Area  - City 1,285 km²  (580 sq mi)  - Urban 5... Location Coordinates Time zone CET/CEST (UTC+1/+2) Administration Country NUTS Region DE6 First Mayor Ole von Beust (CDU) Governing party CDU Votes in Bundesrat 3 (from 69) Basic statistics Area  755 km² (292 sq mi) Population 1,754,317 (11/2006)[1]  - Density 2,324 /km² (6,018...

References

Ultramarine Inc. web page on vessel modeling