what is the structure and the characteristic of submarine?

Question

what is structure and characteristic of submarine?

Answer 1

http://en.wikipedia.org/wiki/submarine

Answer 2

"Modern submarines are usually Cigar-shaped. This design, already visible on very early submarines is officially called a "teardrop hull", and was patterned after the bodies of whales. It significantly reduces the hydrodynamic Drag on the sub if it's submerged, but decreases the sea-keeping capabilities and increases the drag while surfaced. Since the limitations of the propulsion systems of early military submarines forced them to operate most their time on the surface, their hulls were modeled on those of normal ships. Because of the slow submerged speeds of those subs, usually well below 10 kt, the increased drag for underwater travel was considered acceptable. Only late in World War II, when technology enhancements allowed faster and longer submerged operations and increased surveillance by enemy aircraft forced submarines to stay most of their times below the surface, did hull designs become teardrop shaped again, to reduce drag and noise. With nuclear power, submarines can remain submerged nearly constantly, remaining underwater for months at a time. Diesel submarines, by contrast, must periodically resurface or Snorkel to recharge their batteries. Some modern submarines are able to generate Oxygen for their crew by Electrolysis of water.

A raised tower on top of a submarine accommodates the length of the Periscope and electronics masts, which can include Radio, Radar, Electronic warfare, and other systems. In many obsolete boat-shaped classes of submarines (see history, below), the Control Room, or "Conn", was located inside this tower, which was known as the "Conning tower". Since that time, however, the Conn has been located within the hull of the submarine, and the tower is more commonly called the "sail" today. In another interpretation, "conning tower" comes from the English verb "to con", which means "to navigate", indicating the presence of navigational systems in the conning tower. The Conn should not be confused with the "bridge", which is a small, open platform set into the top of the sail used for visual observation while operating on the surface. There may also be an additional closed platform below this with windows and their wipers for running under conditions of bad weather."