Glossary

Deutsch: Druck / Español: Presión / Português: Pressão / Français: Pression / Italiano: Pressione

Pressure in the maritime context refers to the force exerted on objects submerged in water due to the weight of the water above them. It is a crucial concept in understanding the behaviour of vessels, underwater equipment, and marine organisms at various depths. Pressure increases with depth in the ocean, affecting everything from ship hulls to diving operations and submarine design.

Description

In the maritime context, pressure is caused by the weight of the water column pressing down on submerged objects. This pressure increases with depth, as water is much denser than air, leading to rapid increases in force with each additional meter of depth. The relationship between depth and pressure is approximately 1 atmosphere (atm) of pressure increase for every 10 meters (33 feet) of water depth. This pressure is referred to as hydrostatic pressure.

Pressure in the maritime environment affects various aspects of marine engineering and ocean exploration:

• Ships and Submarines: Vessels that operate on or below the water's surface must be designed to withstand the water pressure exerted at their operating depths. Submarines, for example, are built with reinforced hulls to resist the high pressures encountered in deep-sea operations.
• Underwater Equipment: Pressure impacts equipment such as remotely operated vehicles (ROVs), deep-sea sensors, and oil drilling platforms. These devices must be pressure-resistant to function at depth.
• Diving Operations: Divers experience increased pressure as they descend, affecting their bodies and requiring special equipment like pressure-regulated breathing apparatuses to avoid conditions such as decompression sickness (the "bends").
• Marine Life: Many marine species are adapted to live at extreme pressures in the deep ocean, where the pressure can reach several hundred times the atmospheric pressure at sea level.

Application Areas

1. Submarines and Submersibles: Submarines and other underwater vehicles are designed to withstand immense pressures at great depths. Their hulls are made of special materials that prevent them from collapsing under high-pressure conditions.
2. Deep-Sea Exploration: Pressure plays a critical role in deep-sea exploration missions. ROVs and deep-sea drilling equipment must be built to resist crushing forces as they explore the ocean floor at depths exceeding thousands of meters.
3. Marine Construction: Structures like underwater pipelines, oil rigs, and ocean-based wind turbines are subject to water pressure. Engineers must account for these pressures when designing components to ensure structural integrity.
4. Diving: Scuba divers need to understand pressure changes and their effects on the body. Special techniques, such as controlled ascents and the use of mixed gases, are employed to manage the impact of pressure during deep dives.
5. Hydrostatic Testing: Pressure is often used in testing the strength and integrity of marine vessels and pipelines. Hydrostatic testing involves filling these systems with water and applying pressure to check for leaks or weaknesses.

Well-Known Examples

• Bathyscaphe Trieste: The famous deep-sea submersible that descended to the Challenger Deep in the Mariana Trench, the deepest part of the ocean, withstood pressures exceeding 1,000 atmospheres (over 10,000 meters of depth).
• Submarine Design: Military and research submarines, such as the U.S. Navy’s Virginia-class submarines, are constructed with specially reinforced pressure hulls to dive and operate safely at depths of several hundred meters.
• Scuba Diving: Recreational and commercial divers must use pressure-regulated breathing equipment and follow strict decompression procedures to avoid injuries caused by changes in pressure.

Risks and Challenges

• Structural Integrity: High pressure can cause vessels, pipelines, and underwater structures to collapse or fail if not properly designed or maintained. Engineering flaws or material fatigue can lead to catastrophic failures.
• Decompression Sickness: Divers who ascend too quickly after exposure to high pressure can suffer from decompression sickness, where nitrogen bubbles form in the bloodstream, causing severe pain or even death.
• Pressure Crush: Equipment that is not rated for deep-sea pressure can be crushed as the water pressure exceeds the strength of its components, leading to operational failures and potential loss of life or resources.
• Marine Life Impact: Marine organisms adapted to high-pressure environments can die if brought to the surface too quickly, as the rapid change in pressure can damage their tissues.

Similar Terms

• Hydrostatic Pressure: The pressure exerted by a fluid at rest due to the force of gravity, particularly relevant in the maritime context as it applies to water at various depths.
• Barometric Pressure: The atmospheric pressure exerted by the weight of air above sea level. This is lower than the pressure found in the deep ocean but still affects maritime weather and conditions.
• Buoyancy: While not directly pressure, buoyancy relates to the upward force exerted by a fluid that counteracts the weight of an object submerged in it. Buoyancy calculations often involve understanding the pressure differences at various depths.

Summary

Pressure in the maritime context refers to the force exerted by water on vessels, structures, and living organisms submerged in the ocean. It increases with depth, impacting ship design, deep-sea exploration, diving operations, and the construction of underwater infrastructure. While critical for understanding marine environments, pressure poses significant risks, including structural failures, decompression sickness for divers, and challenges for deep-sea equipment. Proper design, materials, and operational procedures help mitigate these risks, ensuring safety and functionality in the maritime environment.

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Weblinks

• kriminal-lexikon.de: 'Druck' in the kriminal-lexikon.de (German)
• fitness-and-health-glossary.com: 'Pressure' in the fitness-and-health-glossary.com
• umweltdatenbank.de: 'Druck' im Lexikon der umweltdatenbank.de (German)
• quality-database.eu: 'Pressure' in the glossary of the quality-database.eu
• top500.de: 'Pressure' in the glossary of the top500.de
• space-glossary.com: 'Pressure' in the space-glossary.com
• environment-database.eu: 'Pressure' in the glossary of the environment-database.eu
• industrie-lexikon.de: 'Druck' in the industrie-lexikon.de (German)
• psychology-lexicon.com: 'Pressure' in the psychology-lexicon.com