Naval aircraft carrier turning at speed; Really Impressive

[kschachn]

Temperature is the least of one’s worries if you walk in front of a pinhole stream at 1200psi…

True except that you can still get burned. We used to have to wear long pants and long sleeved shirts at 130F ambient to do upper boiler atmosphere tests. You were literally standing on top of the operating boiler to do this test. I was a bit younger back then though and it’s why the plant engineers had the summer engineering students do this work.

 

[OVERKILL]

That seems really low. The catapult water tanks were heated to over 600F, so the steam loop from the reactor had to be hotter than that.

I was going by memory for typical power plant temperature, which operate at MUCH lower temperature than fossil plants. CANDU temps are often referred to as "warm soup", lol.

I was a little bit off, I looked it up and:
- CANDU PHT is between 570 and 480F and the secondary loop (which is what we'd be discussing here) is ~480F on the SG outlet and 340F return.

- AP1000 (PWR) PHT circuit is between 615 and 534F. At full plant load the secondary loop is ~520F feed, with no load (hot standby) it's 557F @ 1,106psi. Feedwater temp is 440F.

So, the AP1000 runs a bit warmer than a CANDU, but the secondary side is well short of 600F.

NPP's run lower temps for safety reasons. I'm guessing that the Navy units are perhaps allowed to run a bit hotter?

 

[SubieRubyRoo]

NPP's run lower temps for safety reasons. I'm guessing that the Navy units are perhaps allowed to run a bit hotter?

As long as the reactor coolant pumps are running, they do kinda have an unlimited supply of cooling water…

But that’s mostly a funny, because after we discuss the overall GPM of those pumps (mind-blowing, like most everything else on a nuclear carrier scale is) I have absolutely zero understanding of their operation. I didn’t have to wear a TLD “most” of the time, and even when I did, it was barely above the ship’s baseline.

That TLD comment is in complete contrast to when I was a radiographer in oil & chemical plants for NDT… I worked with some guys who for their New Year’s resolutions would start a betting pool on who could catch the most… some of them topped 15 Rads over the whole year. After 2.5 years, I had matured enough to realize they were nuts and would likely end me up with irreversible damage or federal charges. So I went to Purdue for a BS ECET & MS Tech. Safer that way

 

[OVERKILL]

As long as the reactor coolant pumps are running, they do kinda have an unlimited supply of cooling water…

But that’s mostly a funny, because after we discuss the overall GPM of those pumps (mind-blowing, like most everything else on a nuclear carrier scale is) I have absolutely zero understanding of their operation. I didn’t have to wear a TLD “most” of the time, and even when I did, it was barely above the ship’s baseline.

That TLD comment is in complete contrast to when I was a radiographer in oil & chemical plants for NDT… I worked with some guys who for their New Year’s resolutions would start a betting pool on who could catch the most… some of them topped 15 Rads over the whole year. After 2.5 years, I had matured enough to realize they were nuts and would likely end me up with irreversible damage or federal charges. So I went to Purdue for a BS ECET & MS Tech. Safer that way

Yeah, the pumps are huge! Darlington has 4 pumps that draw something like 10MW each, which is ~13,500HP Each pump draws more than peak output of 150 acres of solar... House load is, IIRC, ~45-50MW. You can see this at Bruce when a unit is plugging along at like 815-820MW and then all of a sudden it's at >880MW because it's on Aux (house load supported by adjacent units) due to maintenance or some other reason.

Edit, here's a Darlington unit (2) on Aux. You can see it drop down to ~850 with the load restored, so that's a 50-60MW house load:

 

[bbhero]

Just to put some perspective on how big that crane is in the Newport News Shipyard.

The 233-Foot Tall, 4600-Ton Crane That Builds Aircraft Carriers

Aircraft carriers are, how to say, big. Building them is a lot easier if you have a really, really big crane. Meet Big Blue. She's the largest crane in the western hemisphere, and she's hard at work piecing together the new Ford-class aircraft carriers in Newport News, Virginia.

gizmodo.com

That massive crane can be easily seen on the James river bridge from the Isle of White county side of the bridge . And that is over 4 miles away from that crane.

 

[Thermo1223]

As long as the reactor coolant pumps are running, they do kinda have an unlimited supply of cooling water…

But that’s mostly a funny, because after we discuss the overall GPM of those pumps (mind-blowing, like most everything else on a nuclear carrier scale is) I have absolutely zero understanding of their operation. I didn’t have to wear a TLD “most” of the time, and even when I did, it was barely above the ship’s baseline.

That TLD comment is in complete contrast to when I was a radiographer in oil & chemical plants for NDT… I worked with some guys who for their New Year’s resolutions would start a betting pool on who could catch the most… some of them topped 15 Rads over the whole year. After 2.5 years, I had matured enough to realize they were nuts and would likely end me up with irreversible damage or federal charges. So I went to Purdue for a BS ECET & MS Tech. Safer that way

Another bit of useless info that lives rent free in my head is I think all modern nuclear subs can go dead silent and use passive convection cooling for the reactor. No pumps or minimal but obviously at a reduced power output.

 

[weaponoffreedom]

 

[4WD]

That massive crane can be easily seen on the James river bridge from the Isle of White county side of the bridge . And that is over 4 miles away from that crane.

The Goliath cranes in Korea are rated to 900 tons - but those are just putting pieces together - weight is one thing - but it’s the size and bulkiness that they manage so well (load sharing/spreading) … Once assembled by them - they have lifted over 42,000 MT with jacks prior to skid off onto a barge …

 

[wwillson]

That seems really low. The catapult water tanks were heated to over 600F, so the steam loop from the reactor had to be hotter than that.

I asked my Nuke friend, who ran a reactor on the Enterprise.

Hot leg primary coolant temperature was 510-515°F with saturated steam at 600 PSIG. The CAT steam box took steam directly off the reactor plant steam headers.

 

[BMWTurboDzl]

So if the mass of water in the bucket actually slows the gpm the bucket should fill faster with the nozzle above. Might try that.

Well I was saying the mass of the water keeps the hose at the bottom of the bucket. You're talking about the mass of water impacting the amount of flow out of the hose.

 

[billt460]

Well I was saying the mass of the water keeps the hose at the bottom of the bucket. You're talking about the mass of water impacting the amount of flow out of the hose.

For what it's worth, I didn't notice any slowing down of the flow when the tip of the nozzle was placed under the surface of the water. I did notice the "thrust" was all but completely diminished instantly, as soon as it was submerged.

To interpret this more accurately, you would have to time the fill of say a 5 gallon bucket with the nozzle both in, then again out of the water.

And even if there is a slight decrease in fill time with the nozzle submerged, it is in no way proportionate to the decrease in nozzle thrust that is instantly experienced as soon as you submerge it. Because once submerged, the thrust of the nozzle is all but completely diminished.

 

[billt460]

You cannot compare this to the clamshell thrust reverser on a jet engine. Because the high speed exhaust gasses being produced are impacting the clamshell, which is attached to the engine.

The nozzle is not "attached" in any way to the surrounding water it is submerged in.

This question would most likely never have come up had there been indoor plumbing around when Isaac Newton came up with this whole, Third Law Of Motion, deal.

 

[OVERKILL]

I asked my Nuke friend, who ran a reactor on the Enterprise.

So roughly the same temp range as the AP1000.