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Old 03-20-2014, 10:47 AM
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Originally Posted by sixshooter
I can see where gobs more power from 2500 to redline would scare you. Most people who choose Roots type blowers for a Miata aren't looking for real power gains. They are just tired of being left behind by four cylinder Camrys in traffic. Congrats, you are as quick as a Camry.

A coal-fired power plant that buys machinery from me was trying for several months to hire any ME for $80k a year before they finally found someone. They are in a rural area where the cost of living is low. But coal has been almost completely shut down by The Administration so the plant has just undergone a tens of millions of dollars reconfiguration to begin burning wood (???) for power generation. They say it is "green energy" but at 80 tractor trailer loads of wood mulch per day, they are going to run out of trees from new development pretty quickly. The plant has only been operational since the first of the year and it is taking most of the land clearing tree debris from a three hour radius to keep it supplied. It is unsustainable unless they start cutting down trees for the sake of powering it. Meanwhile, 45 minutes to the north a nuke plant at Crystal River, Florida has been shut down by Duke energy permanently.
Yep, I am as quick as a Camry, and I'm happy with that! I plan to remove my MP62 for my track days this spring. If I feel I want it after day 1, I'll toss it on that night so I have it for day 2. N/A has better response, weighs less, and won't cook my stock brakes. I'm also still running the stock radiator, but I have done the M-tuned reroute.

Crystal River was, like SONGS, pretty tragic. Their Reactor Containment broke and fixing it was going to cost quite a few Billion. They worked on fixing it for a year or two before the plant got canned.

Unfortunately, we can't just be Russia and run without Containment here...
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Old 03-20-2014, 11:42 AM
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Originally Posted by canyonarrow
He said I'd see turbo plots that are better than mine in every way. That torque curve is nowhere near as flat as mine. You lose.
That IS better in every way, and it's not even the e85 tune with more advanced timing

I fail to see how peaking at 155 ft/lbs @2600 rpm and holding it flat is better than hitting 155 ft/lbs @2600 rpm and still climbing from there. If he wanted to make the torque curve "flat" he could just turn down the boost and dial in the timing map to make the torque curve as flat as your girlfriends ****.
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Old 03-20-2014, 12:01 PM
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Here's a super stupid tiny half-assed turbo setup dyno on 10psi.

It's a lot like the supercharger chart above. Just more.

Attached Thumbnails Upgrading forums...-red%252520miata%252520dyno%2525202010.jpg  
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Old 03-20-2014, 12:09 PM
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Have you tracked it before? If not, probably a good idea to run NA at first. Even with HP, the real speed on the Miata comes from keeping it up in the corners.

BTW, I run an OEM radiator at 200RWHP. I don't have an intercooler. An unblocked OEM radiator with good ducting and a reroute cools well -- good enough for TX.

Comanche Peak is right around the corner from me. So is MSR-C -- and you can drive year-round. Cost of living is low here. Hint. (You do have to deal with Bible-belt nonsense here though -- I think that drove JP nuts when he did a stint in DFW.)
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Old 03-24-2014, 01:43 AM
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Originally Posted by hornetball
Have you tracked it before? If not, probably a good idea to run NA at first. Even with HP, the real speed on the Miata comes from keeping it up in the corners.

BTW, I run an OEM radiator at 200RWHP. I don't have an intercooler. An unblocked OEM radiator with good ducting and a reroute cools well -- good enough for TX.

Comanche Peak is right around the corner from me. So is MSR-C -- and you can drive year-round. Cost of living is low here. Hint. (You do have to deal with Bible-belt nonsense here though -- I think that drove JP nuts when he did a stint in DFW.)
Nope, never tracked before. That's the main reason I figured I'd stay N/A, it's easier to stay out of trouble and have fun. I also don't know what the brake pads are on my car. They could be the originals from Mazda. I'm the third owner, and haven't had to replace them.

I actually just turned down a job offer from Comanche Peak. I know cost of living is low there, and MSR-C looks like a nice track. But they wanted me to take almost a 10% pay cut to go to a two-plant site from a single-plant site; where I would have a refueling outage every 9 months instead of every 24.

I also feel like there's a reason cost of living is low there. Winter may be depressing in Upstate NY, but the crap-brown color of everything in Fort Worth seems depressing year-round. Maybe I'm just not used to it.

I enjoy my drive to work right now. There's hills and curves and beautiful scenery. I don't think I'll ever enjoy the drive out to that plant.
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Old 03-24-2014, 07:53 AM
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Well, it is pseudo-desert here. But the back roads are still fun, speed limits are high and fellow drivers courteous.

We do need a ski mountain though (moved here from Boise).
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Old 03-24-2014, 01:11 PM
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Originally Posted by canyonarrow
edit: Oh, and BWR's are great! More efficient than PWR's, and fewer parts. Way easier to moderate. No Boron. No Pressurizers. No Steam Generators. No Davis-Besse Reactor Head Events. No Three Mile Islands. Much cheaper to operate!
Hehe. Yeah, I understand the plusses. Lower pressure, fewer moving parts, etc. They just weird me out a little, given that active control of some kind is required to drive the control rods upwards into the core during a SCRAM or similar event. A BWR will never be 100% passively safe.






Originally Posted by EO2K
Joe does not own a car anymore, let alone a Miata. In for pics of Joe on a bike in jorts at Watkin's Glen
The car-less-ness is a temporary state of being. Eventually I will probably move out into the 'burbs and require internal-combustion once more. I'm torn right now between desiring the practicality of a PRHT vs. my love of the simplicity of the NA/NB chassis vs. the fact that the 997s are coming down in price.






Originally Posted by canyonarrow
I actually just turned down a job offer from Comanche Peak. I know cost of living is low there, and MSR-C looks like a nice track. But they wanted me to take almost a 10% pay cut to go to a two-plant site from a single-plant site; where I would have a refueling outage every 9 months instead of every 24.

I also feel like there's a reason cost of living is low there. Winter may be depressing in Upstate NY, but the crap-brown color of everything in Fort Worth seems depressing year-round. Maybe I'm just not used to it.

I enjoy my drive to work right now. There's hills and curves and beautiful scenery. I don't think I'll ever enjoy the drive out to that plant.
Ft. Worth ain't too bad. I've spent a lot of time working in the DFW area, and while they definitely don't have the same roads we do in NYS, the place does grow on you. When I first moved out to SoCal from the mid-west, the fact of being in a desert did seem kind of odd at first. But now that I'm back on the commie coast, I really do miss it out there.


Serious question: Does Commanche Peak being a PWR plant significantly affect your decision-making, the amount of training you'd need to make the switch, etc., or are you far-enough removed from operations that it doesn't really matter whether the steam turning the fan is hot or not?
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Old 03-24-2014, 11:05 PM
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Originally Posted by Joe Perez
Hehe. Yeah, I understand the plusses. Lower pressure, fewer moving parts, etc. They just weird me out a little, given that active control of some kind is required to drive the control rods upwards into the core during a SCRAM or similar event. A BWR will never be 100% passively safe.
And gravity makes PWR"s passively safe? They still need to release the rods in an event, which IMO makes them just as failure prone as BWR rods. There are lots of cases of control rods failing to insert at both types of plant.

As far as BWR control rods are concerned, we do have passive nitrogen tanks to supply pressure for inserting them. Each rod has its own little tank, and a few redundant solenoid valves to send that pressure screaming to it's control rod. Those solenoids use power to stay closed; internal springs open them, so if we lose power or a scram signal is sent, as long as one of the springs in one of the valves works, the scram will go off. Since all 100-and-something control rods have their own separate tank and valves, if a few fail, we still get most of the scram. We can then work on manually inserting the other ones if we feel the need. I'm guessing PWR's rely on some kind of solenoid to release the control rods, too.

There's a real benefit in the fact that we boil in the core, with a 'negative void coefficient.' It's the closest we get to passive safety. As you probably know, the core uses water as a moderator. The water slows down neutrons, and uranium likes to absorb slow-moving neutrons for whatever reason. When the water boils, it becomes less dense; and with fewer water molecules there to moderate, power is reduced. That's why we use two 5000 hp Recirculation Pumps to force water into the fuel and push the voids out. If we lose those pumps, the voids will collect around the fuel, and reactivity/power will drop. To assist in this, we have pressure relief valves, which will automatically open at their setpoint (think mechanical BOV's set to 1055 psi). We can open them manually to reduce reactor pressure, therefore increasing the boiling in the core, further reducing power.



Originally Posted by Joe Perez
The car-less-ness is a temporary state of being. Eventually I will probably move out into the 'burbs and require internal-combustion once more. I'm torn right now between desiring the practicality of a PRHT vs. my love of the simplicity of the NA/NB chassis vs. the fact that the 997s are coming down in price.
Come on Joe, wait a year and get an ND!



Originally Posted by Joe Perez
Ft. Worth ain't too bad. I've spent a lot of time working in the DFW area, and while they definitely don't have the same roads we do in NYS, the place does grow on you. When I first moved out to SoCal from the mid-west, the fact of being in a desert did seem kind of odd at first. But now that I'm back on the commie coast, I really do miss it out there.


Serious question: Does Commanche Peak being a PWR plant significantly affect your decision-making, the amount of training you'd need to make the switch, etc., or are you far-enough removed from operations that it doesn't really matter whether the steam turning the fan is hot or not?
I figured I would get used to it eventually. I will miss skiing a lot, but there is the upside of being a short, cheap direct flight from Colorado! My whole family is in Upstate NY, though, which makes it tough (both parents, 3 brothers). We're a pretty close family.

Comanche Peak being a PWR didn't affect my decision at all. It actually sounds great to be able to go everywhere in the Turbine Building, and enter Containment, at power. Since I'm a plant engineer, things wouldn't change too much. Things wouldn't change too much for me at a Fossil Unit, either. The fact that they are a dual-unit site on 18 month cycles is a much bigger contributor.
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Old 03-24-2014, 11:44 PM
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You should start a nuclear engr. thread. I worked with some technicians from a nuke plant a few years back. They never lost that nuclear mindset: take absolutely forever to make a simple decision about nothing, but only after consulting four other people.
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Old 03-25-2014, 09:20 AM
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Originally Posted by canyonarrow
I do have a nice stable job, but our turnover rate is high here, too; and getting higher. My engineering department of about 60 engineers has had 92% turnover in the past 5 years.

Is there something causing your high turnover rate? I work for a power utility and 80% of the work force is within 5 years of retirement. At the rate we are hiring, I might be CEO in 10 years.


No Davis-Besse Reactor Head Events.
that was not an event, we were just applying our transformer replacement policy to the reactor. (if it's on fire, it needs to be replaced!)
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Old 03-25-2014, 04:26 PM
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Can I get the width of your 6UL and your tire specs, looking for something similar for a street setup.
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Old 03-25-2014, 07:01 PM
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Originally Posted by Davezorz
that was not an event, we were just applying our transformer replacement policy to the reactor. (if it's on fire, it needs to be replaced!)
The not-quite-hole in the reactor head at Davis-Besse might not have been an event, but in Sep 1977 they did hold a dress-rehearsal for the Three Mile Island Unit 2 meltdown which would follow two years later.

It's a fascinating story, actually.

Both Davis-Besse 1 and TMI-2 are essentially identical Babcock & Wilcox PWR designs, of the same generation and with roughly the same rated output. And while Davis-Besse is obviously built on an Indian burial ground, this is just too eerie.

The reactor was running at low power, when a transient fault caused the closure of the main feedwater system and a trip. With no feedwater, the steam generators started to boil dry, leading to an overpressure condition that resulted in the opening of the pressurizer PORV. The valve stuck open, causing an accelerated loss of coolant and depressurization of the system. Even worse, the operators at one point shut down the emergency feedwater pumps, confused by ambiguous and misleading core water-level indications. This is more or less exactly the sequence of events which, owing to a few other complicating factors, later led to a de-facto LOCA and meltdown at TMI-2.

Davis-Besse was spared a meltdown through a combination of luck and operators who (mostly) allowed the safety systems to operate normally and correctly identified the faulty PORV and isolated it. There was nothing fundamentally flawed about the design of the B&W core itself, however the instrumentation and user interface of that series are practically a case-study in how not to design critical safety systems.

Last edited by Joe Perez; 03-25-2014 at 11:11 PM.
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Old 03-25-2014, 07:20 PM
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This intro thread has caused the following:
  1. Loss of my productivity
  2. about 50~60 pageviews on wikipedia regarding reactor technology and associated accoutrements
  3. a healthy fear of nuclear reactor "maintenance contractors"

Who the hell thought it was a good idea to falsify inspection documents for reactors?

It sounds like these 1970's era reactors are getting a little long in the tooth. Why are we not building new ones using modern technology and materials? My favorite part of the Davis-Besse article was where they went and bought a used head for a reactor vessel. Like, you know, down at the reactor wrecking yard
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Old 03-25-2014, 07:41 PM
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Originally Posted by EO2K
Why are we not building new ones using modern technology and materials?
Well, that's a two-part answer.

1: Because of fear, hysteria, disinformation, etc. We (the American people) have collectively decided that we prefer slow and invisible poisioning and tens of thousands of fatalities per year from fossil-fuel generation rather than clean, reliable, fossil-free nuclear generation with a very slight risk of a tiny number of fatalities once every few decades.


2: Actually, we are. New CPs stopped dead after the Three Mile Island meltdown, and nothing at all happened for about 30 years. But within the past few years, we have in fact started back up again. Two new units are being constructed at Plant Vogtle in eastern Georgia, plus two more new units at V.C. Summer nuclear plant just north of Columbia, SC, PLUS they're finally going to finish the Watts Bar 2 unit in Rhea County, Tennessee, which was halted in 1988. So that's five new plants expected to come online within a few years.




Artists rendition of the completed Vogtle facility:




Actual photos of Vogtle:










Somewhat NWS video that is worth watching:



(****, language, full-frontal-nudity, and actual truth.)



Thread about progress: https://www.miataturbo.net/current-e...rogress-67014/
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Old 03-25-2014, 10:16 PM
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Originally Posted by Joe Perez
(****, language, full-frontal-nudity, and actual truth.)
I didn't take this warning literally. I should have.
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Old 03-25-2014, 10:40 PM
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Originally Posted by canyonarrow
I'm guessing PWR's rely on some kind of solenoid to release the control rods, too.
In all modern* PWR designs, the neutron-absorbing rod is held to the actuator via an electromagnet. In the event of a loss of electrical power, the magnet de-energizes and the rod simply falls into the core by gravity alone. There is no need to actively "release" the rod, it naturally wants to be in the core and must be actively held up out of it.
* = modern is anything built since the late 1950s


Originally Posted by canyonarrow
There's a real benefit in the fact that we boil in the core, with a 'negative void coefficient.'
I only just noticed this- correct me if I'm wrong, but do not *all* light-water-moderated reactors exhibit a negative void coefficient, be they BWR or PWR?

The real counterpoint here would be graphite-moderated designs (eg: Windscale, Chernobyl).



Originally Posted by canyonarrow
Come on Joe, wait a year and get an ND!
The idea of buying a new* car offends me on general principle. Just because I can afford it does not mean that I desire it. That said, I have actually spent more on a bicycle than on my last Miata.

* = new is anything < 10 years old.
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Old 03-26-2014, 11:57 AM
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Originally Posted by Joe Perez
2: Actually, we are. . . . eastern Georgia . . . just north of Columbia, SC . . . Rhea County, Tennessee.
Hmmm . . . I think I see a pattern here.

Originally Posted by Joe Perez
The idea of buying a new* car offends me on general principle. Just because I can afford it does not mean that I desire it.
That's funny. My personal sweet spot seems to be $3-4K. All my favorite cars seem to be in that range . . . my Sport Fury and both Miatas. Enough that I'm not buying junk but fully depreciated and still wonderful machines.

I do spend a lot more on my wife's cars. But that's a lot cheaper than the alternative.
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Old 03-26-2014, 12:17 PM
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I only just noticed this- correct me if I'm wrong, but do not *all* light-water-moderated reactors exhibit a negative void coefficient, be they BWR or PWR?

The real counterpoint here would be graphite-moderated designs (eg: Windscale, Chernobyl).
I think the coefficient in the BWR would tend to a much larger value, as it is designed to make steam in the reactor vessel. Aren't you usually in big trouble if you have steam voids forming in your PWR? Your reactor output will fall off a little bit, but your control rods are not getting cooled where the steam void forms.


In all modern* PWR designs, the neutron-absorbing rod is held to the actuator via an electromagnet. In the event of a loss of electrical power, the magnet de-energizes and the rod simply falls into the core by gravity alone. There is no need to actively "release" the rod, it naturally wants to be in the core and must be actively held up out of it.

* = modern is anything built since the late 1950s
Wikipedia seems to indicate you can use steam pressure to push the control rods up if you need to. While I would agree gravity is more fail safe system, if you have absolutely no steam pressure, it is probably too late to insert the control rods anyway.
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Old 03-26-2014, 11:06 PM
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Originally Posted by jacob300zx
Can I get the width of your 6UL and your tire specs, looking for something similar for a street setup.
My 6UL's are 15X7's, and my tires are 195/50/15's. They're General Exclaim UHP's, which they don't make anymore. I'll be getting RE-11A's for my next tire. While a lot of people talk about getting 15X8's for street tires, they're a bit more expensive, heavier, and I wasn't sold on the performance improvements of running a rim that wide; at least not on the street. If I want a stiffer sidewall and more grip, I'll get a better tire.

Originally Posted by Davezorz
Is there something causing your high turnover rate? I work for a power utility and 80% of the work force is within 5 years of retirement. At the rate we are hiring, I might be CEO in 10 years.



that was not an event, we were just applying our transformer replacement policy to the reactor. (if it's on fire, it needs to be replaced!)
Yeah, retirement is a big issue. The industry kicked off about 40 years ago, and most of the people in it are getting right to retirement age. Also, a lot of people dislike my company. It's actually improving, though.

We actually just used that same replacement policy to one of our main station transmformers last year! I guess you could see the smoke from the transformer from 10 miles away. I guess buying it from Brazil was a poor decision.

Originally Posted by Joe Perez
The not-quite-hole in the reactor head at Davis-Besse might not have been an event, but in Sep 1977 they did hold a dress-rehearsal for the Three Mile Island Unit 2 meltdown which would follow two years later.

It's a fascinating story, actually.

Both Davis-Besse 1 and TMI-2 are essentially identical Babcock & Wilcox PWR designs, of the same generation and with roughly the same rated output. And while Davis-Besse is obviously built on an Indian burial ground, this is just too eerie.

The reactor was running at low power, when a transient fault caused the closure of the main feedwater system and a trip. With no feedwater, the steam generators started to boil dry, leading to an overpressure condition that resulted in the opening of the pressurizer PORV. The valve stuck open, causing an accelerated loss of coolant and depressurization of the system. Even worse, the operators at one point shut down the emergency feedwater pumps, confused by ambiguous and misleading core water-level indications. This is more or less exactly the sequence of events which, owing to a few other complicating factors, later led to a de-facto LOCA and meltdown at TMI-2.

Davis-Besse was spared a meltdown through a combination of luck and operators who (mostly) allowed the safety systems to operate normally and correctly identified the faulty PORV and isolated it. There was nothing fundamentally flawed about the design of the B&W core itself, however the instrumentation and user interface of that series are practically a case-study in how not to design critical safety systems.
Just to add to that, Three Mile Island didn't find realize their PORV was stuck open. This is why Operating Experience is such a huge deal in Nuclear Power; there were several stuck PORV events before TMI (Davis Besse included) that, had they known about the issue with those valves, they could have mitigated their accident with no problems.

Originally Posted by EO2K
This intro thread has caused the following:
  1. Loss of my productivity
  2. about 50~60 pageviews on wikipedia regarding reactor technology and associated accoutrements
  3. a healthy fear of nuclear reactor "maintenance contractors"

Who the hell thought it was a good idea to falsify inspection documents for reactors?

It sounds like these 1970's era reactors are getting a little long in the tooth. Why are we not building new ones using modern technology and materials? My favorite part of the Davis-Besse article was where they went and bought a used head for a reactor vessel. Like, you know, down at the reactor wrecking yard
Look up the SL-1 story (Stationary Low-Power Reactor 1). That is my favorite. Prompt-criticality is pretty terrifying.

The cost of building a new reactor, back in the 60's/70's, was huge. Today, there are more requirements and red tape than you can possibly imagine, which has made the cost of building new ones harder and harder to justify.

The main issue right now is Hydrofracking. Natural gas prices are so low that power prices have dropped, making nuclear plants unviable. Hell, Vermont Yankee is shutting down this fall and Kewaunee shut down two years ago just because the already-built plants were no longer making profit, and are not projected to in the near future. I still think these plants should have gotten some sort of subsidy, since they are completely carbon neutral.

The reason the new plants are going up where they are is because those are places in the country that are pro-nuclear, and power prices are high enough there for it to make sense.

Originally Posted by Joe Perez
In all modern* PWR designs, the neutron-absorbing rod is held to the actuator via an electromagnet. In the event of a loss of electrical power, the magnet de-energizes and the rod simply falls into the core by gravity alone. There is no need to actively "release" the rod, it naturally wants to be in the core and must be actively held up out of it.
Well, the rod is held by an electromagnet; much like our solenoid valves are held shut by an electromagnet. I personally prefer the oomph of high-pressure nitrogen from below to relying on that wuss gravity. Control rod binding is a real problem; especially if the core has gotten hot enough that things start to warp.

Originally Posted by Joe Perez
I only just noticed this- correct me if I'm wrong, but do not *all* light-water-moderated reactors exhibit a negative void coefficient, be they BWR or PWR?
PWR's would have a negative void coefficient; the problem is, they run borated water (aka boric acid) through the core, a neutron absorber. When you boil water, the dissolved boron falls out. This is why you never want to boil water inside a PWR core.

BWR's have emergency Boron injection systems, to inject sodium pentaborate into the core to 'poison' it and kill the reaction. Otherwise, we run pure distilled water (running borated water wouldn't work for us since we boil water by design).

Last edited by canyonarrow; 03-26-2014 at 11:26 PM.
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Old 03-27-2014, 08:47 AM
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We actually just used that same replacement policy to one of our main station transmformers last year! I guess you could see the smoke from the transformer from 10 miles away. I guess buying it from Brazil was a poor decision.
When we lose a 500 MVA class transformer, it typically burns for about 5-7 days. Buying one from Brazil makes more sense when you consider you only have about 3 choices in the U.S. for large power transformer production. and none of them build shell-form transformers, which I assume you wanted.

On a related note, one of our steel mills bought 2 200 MVA core form transformers from a maker in Taiwan. It literally showed up at their sub as a pile of parts with no assembly instructions. Apparently no one who knew how to build it could speak English. Much consternation ensued.
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