Re: New train tested at 348km/h in Italy. Question of finance


"Mxsmanic" <mxsmanic@xxxxxxxxx> wrote in message
news:itg0j19hh0840ko83s6mhmudnsdajpll56@xxxxxxxxxx
> Keith W writes:
>
>> They didnt realise how bad it was, when they tried to sell the design
>> to the CEGB here in the UK our reactor physicists were horrified
>> at the basic flaws
>
> And didn't the attitude of the UK physicists make them wonder?
>

No - the party said it was safe so rocking the boat would be
a bad idea.

>> Chernobyl went up with an explosion that was large enough to crack open
>> the reactor, destroy most of the building and spread fission products
>> over
>> a large area. The fact that the explosion was caused by hydrogen
>> wasnt much comfort to thopse affected.
>
> A thermonuclear detonation would have vaporized a lot of those
> residents, so I guess no comforting would then be necessary.
>

Fission reactors dont typically give rise to fusion explosions


>> Indeed but it was a close run thing, when they poured water into
>> the burning core an explosion was a definite possibility. That
>> incident scared the crap out of the reactor designers over here
>> and we never built another direct cycle reactor.
>
> I'm surprised it was designed that way to begin with. I'd expect
> better cooling provisions (especially for emergencies) and better
> containment. And maybe an inert atmosphere to discourage combustion
> as well (since graphite burns quite well).
>

When Pile No 1 was built the cold war was at its height
and producing weapons grade plutonium was seen as a
matter of the utmost importance, especially once the
Soviets exploded their first weapons. Risks were taken
as it was believed the risk of not having an independent
deterrent was even higher. Note that both the Soviets and
Americans also used open cycle cooling systems in their
first generation reactors. The US reactors at Hanford dumped their
cooling water straight into the Columbia river.

The follow on designs, such as Calder Hall did indeed
have better cooling systems and used CO2 as the cooling medium

>> The main thing that mitigated the results of the Windscale fire
>> was the filter assembly fitted to the exhaust stack which trapped
>> a high percentage of the emissions. That safety device was
>> called Cockroft's Folly when first installed as most of the
>> engineers didnt think it necessary. Fortunately Sir John Cockroft
>> stuck to his guns on the issue and they were in place.
>
> So why did anything actually get through? Was there a flaw in the
> filter?
>

No filter is 100% effective and it was designed to handle the
contamination of a burst fuel pin , not a fire that fully engaged
the entire reactor.

Keith


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