Sunday, March 4, 2012

Pacific Vortex: conventional nuclear submarine and more

pg 101

Her length was at least twice that of a conventional nuclear submarine.
A nuclear submarine is a submarine powered by a nuclear reactor. The performance advantages of nuclear submarines over "conventional" (typically diesel-electric) submarines are considerable: nuclear propulsion, being completely independent of air, frees the submarine from the need to surface frequently, as is necessary for conventional submarines; the large amount of power generated by a nuclear reactor allows nuclear submarines to operate at high speed for long durations; and the long interval between refuellings grants a range limited only by consumables such as food.

Current generations of nuclear submarines never need to be refueled throughout their 25-year lifespans. Conversely, the limited power stored in electric batteries means that even the most advanced conventional submarine can only remain submerged for a few days at slow speed, and only a few hours at top speed; recent advances in air-independent propulsion have eroded this disadvantage somewhat. The high cost of nuclear technology means that relatively few states have fielded nuclear submarines. Some of the most serious nuclear and radiation accidents in the world have involved Soviet nuclear submarine mishaps.

Technology
The main difference between conventional submarines and nuclear submarines is the power generation system. Nuclear submarines employ nuclear reactors for this task. They either generate electricity that powers electric motors connected to the propeller shaft or rely on the reactor heat to produce steam that drives steam turbines (cf. nuclear marine propulsion). Reactors used in submarines typically use highly enriched fuel (often greater than 20%) to enable them to deliver a large amount of power from a smaller reactor and operate longer between refuelings -- which are difficult due to the reactor's position within the submarine's pressure hull.

The nuclear reactor also supplies power to the submarine's other subsystems, such as for maintenance of air quality, fresh water production by distilling salt water from the ocean, temperature regulation, etc. All naval nuclear reactors currently in use are operated with diesel generators as a backup power system. These engines are able to provide emergency electrical power for reactor decay heat removal, as well as enough electric power to supply an emergency propulsion mechanism. Submarines may carry nuclear fuel for up to 30 years of operation. The only resource that limits the time underwater is the food supply for the crew and maintenance of the vessel.

The stealth weakness of nuclear submarines is the need to cool the reactor even when the submarine is not moving; about 70% of the reactor output heat is coupled into the sea water. This leaves a "thermal wake", a plume of warm water of lower density which ascends to the sea surface and creates a "thermal scar" observable by thermal imaging systems, e.g. FLIR.

A Sherlock Holmes you ain't.
Sherlock Holmes is a fictional detective created by Scottish author and physician Sir Arthur Conan Doyle. The fantastic London-based "consulting detective", Holmes is famous for his astute logical reasoning, his ability to take on almost any disguise, and his use of forensic science skills to solve difficult cases.

Holmes, who first appeared in publication in 1887, was featured in four novels and 56 short stories. The first novel, A Study in Scarlet, appeared in Beeton's Christmas Annual in 1887 and the second, The Sign of the Four, in Lippincott's Monthly Magazine in 1890. The character grew tremendously in popularity with the first series of short stories in Strand Magazine, beginning with A Scandal in Bohemia in 1891; further series of short stories and two novels published in serial form appeared between then and 1927. The stories cover a period from around 1880 up to 1914.

All but four stories are narrated by Holmes's friend and biographer, Dr. John H. Watson; two are narrated by Holmes himself ("The Blanched Soldier" and "The Lion's Mane") and two others are written in the third person ("The Mazarin Stone" and "His Last Bow"). In two stories ("The Musgrave Ritual" and "The Gloria Scott"), Holmes tells Watson the main story from his memories, while Watson becomes the narrator of the frame story. The first and fourth novels, A Study in Scarlet and The Valley of Fear, each include a long interval of omniscient narration recounting events unknown to either Holmes or Watson.

"It'll be dark soon and if there's something rotten in Denmark, we've got to find out damned quick."
The Shakespeare play Hamlet takes place in Denmark. One of its most famous lines is delivered by a character named Marcellus in Act 1: "Somethng is rotten in the state of Denmark."

People have been paraphrasing it ever since to mean something wrong anywhere - from a business to a family unit and so on.

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