Re: Renewable energy alternative

From: daestrom (daestrom_at_NO_SPAM_HEREtwcny.rr.com)
Date: 06/26/04 

Date: Sat, 26 Jun 2004 14:30:18 GMT

"Tim Keating" <NotForJunkEmail@directinternet11.com1> wrote in message
news:o9uod0hd3tao0vs582tejad78fl24uun9u@4ax.com...
> On Fri, 25 Jun 2004 18:50:58 GMT, "daestrom"
> <daestrom@NO_SPAM_HEREtwcny.rr.com> wrote:
>
> >
> >"Tim Keating" <NotForJunkEmail@directinternet11.com1> wrote in message
> >news:bprnd0do4nmt8en5cc0ro9r6r2jts2r3bp@4ax.com...
>
> >> Potential heat energy in excess of 50 tons of TNT all would be
> >> released in a instant. That would be enough to destroy the inner
> >> workings of almost any reactor.
> >
> >Again with the '50 tons of TNT'. Lets see some calculations, not
hyperbole.
>
> http://www.nuke.hun.edu.tr/english/links/pwr.html
>
> Reference Design ........ Westinghouse
> System (reactor station) Sequoyah (TVA)
> Gross thermal power, 3411 MW(th)
> Net electrical power, 1148 MW(th)
> Efficiency (%) , 33.5
> Primary coolant , 306000 L
> Inlet temp, 286C
> Ave. outlet temp, 324C
>
> 306000 L of water * 1000 gr/L * 300C(average temp) * 1Calorie/gr*C
> * 4.1855 J/calorie == ~3.842 x 10^11 Joules.
>
>
> http://www.matter-antimatter.com/energy.htm
> One Ton TNT explosive produces 4.18 x 10^9 Joules of energy
>
> (~3.842 *10^11) / (4.18 * 10^9) == ~91.9 Tons of TNT..
>
> This doesn't account for all the heat energy stored in materials other
> than the primary coolant.
>
> >And 'released in a instant' isn't correct either. A complete shear of
the
> >largest coolant piping so that water can discharge from both sides of the
> >break takes on the order of 30 seconds to discharge all the coolant. A
TNT
> >explosion would be over in milliseconds. Any clue as to how that time
> >difference plays out in your scenario??
>
> Prove it..

What, you want me to create a LOCA?? Since it's clear you've never studied
the subject, any proof I offer would be well over your head.

> A major break in a 40"+ line (ID) @ >2000 PSI can move a lot of
> water in a hurry.

Problem is, the water at the break doesn't *stay* water. As you've pointed
out, it begins to flash to steam (about 60% of it). And the steam/water mix
forms a compressible fluid that has different flow properties than cold
water. Look up 'choked compressible flow'. Any good engineering university
will have the information.

You'll find that with steam, once the downstream pressure drops below about
56% of the upstream pressure (the so-called 'critical pressure ratio'), a
further drop in pressure does *not* increase the flow rate. A shock wave is
established in the outlet piping and no further drop in downstream pressure
can affect the flow rate upstream of the shockwave.

This severly limits the flow rate out even a large pipe end.

When it is a steam water mixture (as it would be in this case), the problem
is even more complicated. As the pressure on the fluid drops while flowing
from the vessel through the pipe to where the break occurs (even if right at
the nozzle, a very *short* pipe), some of the water starts flashing to
steam. As the pressure drops further while flowing towards the break, more
and more of the water flashes. By the time it reaches the containment
pressure about 60% has flashed to steam and the remaining water is so cooled
it cannot flash. So as the fluid flows towards the break, its specific
volume is constantly rising and its temperature is constantly falling.

There have been many studies of exactly this type of flow and the phenomenon
is well documented. Apparently you haven't bothered to look or you would
have found it.

> 2000 PSI water, (effective depth 4,400 feet) can flood a submarine
> in a instant.

Cold ocean water does not suffer from flashing to steam, so it remains a
liquid as it flows in. Hence it is not limited by the same compressible
fluid flow phenomenon. An irrelevent comparision done by a non-engineering
type that doesn't know the difference and has never studied fluid flow.

> It also turns scuba tanks with lost valves into projectiles capable
> of going thru engine blocks.

Not through 'engine blocks'. Concrete blocks, which are hollow. And scuba
tanks have air in them, not cold or hot water. Because of the neck holding
the valve, the air also undergoes the same limitations as steam (although
the critical pressure ratio is slightly different for air as it is for
steam). The high velocity causes the rocketing affect, and the choked
compressible flow prevents it from exiting all in an instant. Ask anyone
who's ever witnessed a scuba tank losing its valve and ask them how long it
took for the air to bleed out. It wasn't an 'instant'. Then consider the
ratio between the valve opening and the bottle size and the ratio between a
cold-leg pipe and the rest of the RCS system.

>
> >> No, 1/2 the guts of the reactor will likely end up on the containment
> >> floor. The reactor pressure vessel will likely rip from it mounts and
> >> bounce around like a balloon loosing it's air. It may even breach
> >> the secondary containment ALL by ITSELF.
> >
> >You really are clueless. The mountings of the RPV are designed for just
> >such 'reaction forces' occuring at the same time as the '100-year
> >earthquake' occurs.
>
> Only the blind have faith... and You are fairly blind...
>
>
http://www.nrc.gov/reading-rm/doc-collections/gen-comm/gen-letters/1978/gl78002.html
>
> "On May 7, 1975, the NRC was informed by Virginia Electric & Power
> Company that n asymmetric loading on the reactor vessel supports
> resulting from a postulated reactor coolant pipe rupture at a specific
> location (e.g., the vessel nozzle) had NOT been considered by
> Westinghouse or Stone & Webster in the original design of the reactor
> vessel support system for North Anna, Units1 and 2. "

What a BS bit of selective reading/quoting.

>From the *SAME* report, in the third paragraph...

"Subsequently in June 1976, the NRC staff informed each PWR licensee that a
reassessment of the reactor vessel support system design for each of its
facilities was required."

And further....
"Please respond within 30 days of receipt of this letter, indicating your
intent to proceed with an evaluation of the overall asymmetric loss of
coolant
accident (LOCA) loads as described herein."

So, those of us that are *not* blind, and can read the whole page can see
that North Anna discovered a problem in their analysis on their own and
reported it to the NRC in 1975. The NRC took the problem seriously and
required all PWR's to ensure such analysis was performed. Did you bother to
look up the results of those analysis?? Probably not.

You're the one that has very selective vision. You see one paragraph in a
report and quickly stop reading because you might learn something that
doesn't fit into your view of the world. Pity

daestrom

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