Tehdyt toimenpiteet

Ships and computational fluid dynamics

Ship design involves many computational challenges. By utilizing virtual prototypes and computational fluid dynamics, it is possible to study situations that would be dangerous, expensive or impossible to study in real life.

When computer models can create a virtual ship prototype that behaves authentically, the design and testing of vessels becomes faster and cheaper. A well-designed ship is safe for passengers, cargo and the environment.

During the design stage, the ship is described by means of a three-dimensional computational model that includes all of its load-bearing structures. The hull of a vessel alone may have over 100,000 components; this makes for complex models. A large vessel may require even hundreds of component models so that all details can be dimensioned reliably.

New, ever faster and larger vessels mean more stringent requirements for the design of hull constructions. A factor affecting the strength of structures is vibration. All structures vibrate and each structure has its own specific frequency, which depends on factors such as the mass of the structure. The strength calculation of ship models also involves the study of vibrations arising, for instance, from the ship’s engine and propeller. The ship’s structures must be dimensioned so that their specific frequency is not the same as that of the engine or the propeller. If the frequency is the same, structures start to resonate and may break.

Lightweight structures are favored in order to reduce fuel consumption. The shape of the hull should also cause as little resistance as possible in water; for instance, large tankers use most of their fuel to overcome the resistance of water. By simulating the flow field surrounding the hull, it is also possible to study the waves caused by the ship’s movements. Modeling provides information about the impacts of waves on the maneuverability of the vessel.

As the sizes and speeds of ships increase, so do the harmful consequences of accidents. Apart from passengers, the crew and the cargo, the environment is also at risk. A torn side may cause an oil disaster. In Finland’s rocky and narrow navigation routes, running aground presents the greatest risk. Computational models can simulate a vessel running aground and the factors affecting the situation. When these factors are known, ship structures can be designed so as to minimize the effects of touching ground; this increases their safety.

Cruise vessels are especially demanding to design. They contain many open, multi-deck spaces that are challenging in terms of strength requirements. Moreover, particular attention is paid to the comfort of traveling. This means, among other things, that every effort is made to eliminate the noise and vibration caused by engines.

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Tehdyt toimenpiteet

Ships and computational fluid dynamics


Sisältö Methods of computational science Applications of scientific computing Modeling the universe Ships and computational fluid dynamics Protein research Drug design Speech recognition and synthetic speech Modeling the human body Modeling in geosciences Geographic information systems Genotype and bioinformatics Grand Challenge research projects in CSC magazines Supercomputers and grids	Tehdyt toimenpiteet Tämä sivu suomeksi Ships and computational fluid dynamics Ship design involves many computational challenges. By utilizing virtual prototypes and computational fluid dynamics, it is possible to study situations that would be dangerous, expensive or impossible to study in real life. When computer models can create a virtual ship prototype that behaves authentically, the design and testing of vessels becomes faster and cheaper. A well-designed ship is safe for passengers, cargo and the environment. During the design stage, the ship is described by means of a three-dimensional computational model that includes all of its load-bearing structures. The hull of a vessel alone may have over 100,000 components; this makes for complex models. A large vessel may require even hundreds of component models so that all details can be dimensioned reliably. New, ever faster and larger vessels mean more stringent requirements for the design of hull constructions. A factor affecting the strength of structures is vibration. All structures vibrate and each structure has its own specific frequency, which depends on factors such as the mass of the structure. The strength calculation of ship models also involves the study of vibrations arising, for instance, from the ship’s engine and propeller. The ship’s structures must be dimensioned so that their specific frequency is not the same as that of the engine or the propeller. If the frequency is the same, structures start to resonate and may break. Lightweight structures are favored in order to reduce fuel consumption. The shape of the hull should also cause as little resistance as possible in water; for instance, large tankers use most of their fuel to overcome the resistance of water. By simulating the flow field surrounding the hull, it is also possible to study the waves caused by the ship’s movements. Modeling provides information about the impacts of waves on the maneuverability of the vessel. As the sizes and speeds of ships increase, so do the harmful consequences of accidents. Apart from passengers, the crew and the cargo, the environment is also at risk. A torn side may cause an oil disaster. In Finland’s rocky and narrow navigation routes, running aground presents the greatest risk. Computational models can simulate a vessel running aground and the factors affecting the situation. When these factors are known, ship structures can be designed so as to minimize the effects of touching ground; this increases their safety. Cruise vessels are especially demanding to design. They contain many open, multi-deck spaces that are challenging in terms of strength requirements. Moreover, particular attention is paid to the comfort of traveling. This means, among other things, that every effort is made to eliminate the noise and vibration caused by engines.