vina wrote:Turbo Electric propulsion is not high tech in that sense. To get a sense of the circuit used in nuclear subs heres a good site on a pressurized water reactor Turbo electric system in an nuclear sub :
http://www.fas.org/man/dod-101/sys/ship ... actor.html
What you posted is the conventional, directly coupling turbine to shaft mechanical linkage thing. The electric motor you see in the figure is the back up thing to turn the shaft from battery power as a standby.
What we mean by direct electric drive is no mechanical linkage, between turbine and prop shaft. It is like a convential submarine in that respect with a main propulsion motor, with the diff being the electricity to drive the motor is generated by a nuclear reactor driven a generator , instead of surfacing/snorkeling and using diesels to charge the batteries.
'Second indigenous nuke sub will be ready soon'
By Ritu Sharma, New Delhi, Aug 18 : India's second indigenous nuclear-powered submarine will be ready soon and will take less time from launch to induction than the first one, says a retired Indian Navy officer who was associated with the top secret project since its inception.
"The second one will be ready and will take lesser time," Vice Admiral (retd.) Mihir K. Roy told IANS in an exclusive interview.
Roy, who is now 84, was the first head of the Advanced Technology Vessel (ATV) that was launched in 1984 and guided it during its first four years. He has been involved in all the back room negotiations with the then Soviet Union, which assisted in the project. He is now director of think tank Society for Indian Ocean Studies.
Roy said the disintegration of the Soviet Union in 1991 delayed the ATV project, under which India aimed to initially design and construct three nuclear-powered combat submarines within the country.
The first vessel, INS Arihant, was launched into the waters July 26. When she is inducted into service after three-years of sea trials, India will became only the sixth country in the world after the US, Russia, Britain, France and China to be capable of designing and constructing nuclear-powered nuclear submarines.
"We were going fast (on the project). But there was a long delay. Then the USSR fell and there was tremendous social, political and technological changes in the country. All contracts (on the ATV project) were changed," Roy said.
"In 2004, Russia stabilised and we signed fresh contracts in dollars. Money was a problem for them because they (Russians) were short of dollars," he added.
The Soviet Union had in 1981 offered to help with the design and construction of a nuclear submarine. In 1988, it had also leased a nuclear submarine, INS Chakra, for five years to enable the Indian Navy, its first batch of officers and sailors, in operating such vessels.
The ATV project was made successful by the close partnership of the Defence Research and Development Organisation (DRDO), the Department of Atomic Energy (DAE) and other public and private sector undertakings.
The project was conceptualised around the same time as those to produce an indigenous light combat aircraft (LCA) and a main battle tank MBT). Both these projects have suffered heavy cost and time overruns, making the launch of INS Arihant a "historic milestone" for the Indian Navy.
"I said that I wanted to report directly to the defence minister, with no interference from secretaries and bureaucrats. It worked. Decisions were made across the table," said Roy, a submariner and former chief of the Eastern Naval Command.
He noted that extra security precautions had to be taken to maintain the secrecy of the project to prevent triggering an arms race on the subcontinent.
"We did not even have a name plate (outside the office). Nobody in my family, not even my wife, was aware what I was doing. On July 26 (when INS Arihatn was launched) my
grandchildren said: 'You never told us!' " Roy said.
"I got the dry docks (at the Visakhapatnam Ship Building Centre) covered; otherwise satellites would have spotted the vessel and taken pictures," Roy reminisced, adding: "I also got the dry docks lengthened."
!