Rocks & mirror

WÄRTSILÄ
Encyclopedia of Marine and Energy Technology

D

348 results

Directional drilling

energy

Directional drilling (or slant drilling) is the practice of drilling non-vertical wellbores.

Direct-printing telegraphy

marine

Automated telegraphy techniques which comply with the relevant recommendations of the International Radio Consultative Committee (CCIR), (SOLAS).

Disabled ship

marine

A damaged or impared vessel not able proceed by its own.

Disc grinder

marine

Any machine that grinds by the action of a rotating disc.

Discharge

marine

Any release from a ship including any escape, disposal, spilling, leaking, pumping, emitting or emptying.

Discharge book

marine

An essential document for officers and seamen as it serves an official certificate confirming their sea experience in the employment time.

Discharge rate

energy

The discharge rate is defined as the steady current in amperes (A) that can be taken from a battery of defined capacity (Ah) over a defined period(h).

Discharges

marine

Any piping leading through the ship sides for conveying bilge water, cooling water, drains, etc.

Disconnector

energy

In electrical engineering, a disconnector, disconnect switch or isolator switch is used to ensure that an electrical circuit is completely de-energized for service or maintenance.

Discontinuity

marine

An interrption of the typical structure of a material, such as lack of homogeneity in its mechanicall, metallurgical, or physical characteristics. A discontinuity is not necessarily a defect.

Discreet Security Alert System

marine

The purpose of this system is to send a covert signal from a ship which will be not obvious to anyone on the ship who is not aware of the alert system.

Disembark

marine

Refers to any time that the crew leave the ship, be it a port call or final destination.

Dish Stirling

energy

A stand alone parabolic reflector which produces temeperatures in a working fluid up to 700 °C (1,292 °F).

Dispatchability

energy

The ability of a power plant to increase and decrease output quickly on demand.

Dispatchable generation

energy

Electricity sources that can be brought online on demand.

Dispersion (water waves)

energy

In fluid dynamics, dispersion of water waves generally refers to frequency dispersion, which means that waves of different wavelengths travel at different phase speeds.

Dispersion relation

energy

In the physical sciences and electrical engineering, dispersion relations describe the effect of dispersion on the properties of waves in a medium.

Displacement

marine

It is the weight of water displaced by this vessel at any waterline. It is the product of the volume of its underwater portion and the density of the water in which it floats.

Displacement curve

marine

A curve showing the displacement of a vessel in fresh or salt water at any draft.

Displacement height

energy

The height above ground level where wind speed is theoretically zero based on the effects of ground cover.

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