Hi dear
@Oscar
Except the para I have quoted above,rest everything seems fine however if we note carefully,there are a lot of "ifs" and "buts" or in short speculations,there is nothing definite in what you have mentioned above. I happen to know a couple of things pertaining to nuclear plants as I have couple of my batch mates in BARC reactor divison--(kindly note BARC has various type of reactor projects going on from PHWR,LWR to fast breeder reactors and now recently AHWRs as well). Designing your own reactor is one thing and miniaturizing it and making it sea worthy is QUITE ANOTHER! Lets be brutally honest,and instead of living in fancies and drooling over some un-substantiated reports,lets for now focus on facts at hand--pakistan hasnt really designed her own nuclear power plant for generating "energy". Pakistan has couple of plutonium and experimental neutron reactors whose origin is pretty much unknown given the scarcity of published literature.
First step in design of a nuclear submarine is mastering the power plant--there is no short cut--you have to master the design. The reactor needs to be validated in simulations which paves the way for the construction of a land based prototype.The data gathered over years of running the land based replica of your submarine reactor gives enough confidence in design and only then is reactor finally engineered into the submarine hull-- this whole process takes at least a decade or more!Pakistan has no land based prototype running that might indicate the possibility of a nuclear submarine reactor being seriously pursued by PN.
I will briefly highlight some of the challenges associated with design of sea going reactors--these are in indian context as discussed in various open seminars and lectures--kindly note it is equally true in the context of pakistan!
1)First to design a sea going reactor(light water moderated as against heavy water moderated)--one would need to establish reactor physics and required metallurgy in the country.Light water reactors traditionally occupy lesser space and are relatively straight forward in design. The down-side though is ,they require slightly higher degree of enrichment vis-a-vis PHWRs that consume natural uranium. In case of submarine reactors though,the enrichment level is way more high than a land based LWR designed for commercial purposes. Higher the enrichment--longer will the endurance of the sub.
2)In case of land based LWRs the power is generally gradually increased to full capacity however in subs the requirement is such that reactor might have to be reved upto full power setting in a very short span of time--for instance during initial accelerations or running away from enemies. This might seem easy at first glance but requires extensive modifications in the design to enable fast building up of power
3)Submarine reactor should be able to withstand shocks and lateral forces that might result from an explosion etc.It is speculated that the reactor core of Oscar-2 class russian SSGN could withstand a g force of 50!
4)To construct the reactor,country must have established FORGING capabilities to forge reactor pressure vessel,pressurizers,turbines,allied control systems etc etc.
Submarine is just the platform and that is useless without itz primary armament.Pakistan would have to design her own SLBMs and master the cold launch philosophy.Again,pakistan doesnt have a SLBM program going on right now. It takes decades to design and field a reliable SLBM--it is not as easy as lets say land based missiles. Your designers would run into same kind of problems, Indian designers ran into almost 10 years back and those were related to a lot of issues ranging from lowering the weight by using composites,complexities in cold launch to storing liquid fuel for RCS(REACTION CONTROL SYSTEM).
And lastly the r&d cost of a nuclear submarine exceeds $3bn--kindly Note it doesn't include the cost of establishing a production line or whole lot of nuclear engineering and support faculties at the harbour. After spending billions of dollars into nuclear submarine program India has only one yard capable of supporting nuclear submarine or has the requisite nuclear engineering set up.How do you think Pakistan would deal with this particular issue?I don't think there is any yard in Pakistan that has technical know how to support or construct a nuclear submarine.
On a serious note, does Pakistan have a under water pontoon from which to launch the experimental SLBM ?