04-03-2010, 12:45 PM
AIR INDEPENDENT PROPULSION SYSTEM FOR SUBMARINES
ABSTRACT
Air independent propulsion (AIP) system is a term that encompasses technologies, which allow a submarine to operate without the need to surface or use a snorkel to access atmospheric oxygen. The term usually excludes the use of nuclear power, and describes augmentation or replacing the electric propulsion system of nonnuclear vessels. AIP is usually implemented as an auxiliary source. Most such systems generate electricity which in turn drive an electric motor for propulsion or recharging the submarine™s batteries .The submarine™s electrical system is also used to provide hotel services-ventilation, lighting, heating etc “ although this consumes a small amount of power compared to that required for propulsion. A benefit of this approach is that it can be retrofitted into existing submarine hulls by inserting an additional hull section. AIP does not normally provide the endurance or power to replace the atmospheric dependent propulsion, but allows it to remain submerged longer than a more conventionally propelled submarine. A typical conventional power plant will provide 3MW maximum, and an AIP source around 10% of that. A nuclear submarine™s propulsion plant is usually much greater than 20MW