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It's toxic, a pain to work with, and you need special stainless steel tools to do anything with it
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Jan 3, 2018 17:10
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telcoM posted:I once looked for a substance that would have higher specific heat capacity than water. It looks like liquid hydrogen would have that property, but its other properties would make it a thread-appropriate comedy option. No other chemical element nor the simple compounds listed in my university-student-level book of tables even came close. Large generators (like those found in nuclear power plants) use gaseous hydrogen for cooling. Pretty neat system with very expensive gaskets.
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Jan 3, 2018 18:28
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Liquid metals in general have lower heat capacity than water, but they also have a much faster conduction coefficient. So basically, if you can keep them pumped fast enough that the coolant stays well below the temp of whatever you're cooling, they actually can out perform water, since it sucks up whatever heat it can nigh instantly before carrying it away. That's a big "if" though, and aside from mercury most liquid metals necessarily have to operate at very high temps. Iirc there's been research on using them to run nuclear reactors ultra hot (can't have a steam explosion if there's no water) for greater efficiency, but nothing that's made it even as far as the industrial scale prototype phase.
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Jan 3, 2018 18:38
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Enourmo posted:Liquid metals in general have lower heat capacity than water, but they also have a much faster conduction coefficient. So basically, if you can keep them pumped fast enough that the coolant stays well below the temp of whatever you're cooling, they actually can out perform water, since it sucks up whatever heat it can nigh instantly before carrying it away. The FFTF facility in Washington State was a reactor cooled with liquid sodium. It was used for research and medical isotope production before having its primary cooling loops cut open 10 or so years ago, exposing it to air and permanently disabling it.
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Jan 3, 2018 18:44
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Thread bout to become a FOOF thread.
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Jan 3, 2018 18:52
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The Russian Alfa-class nuclear subs https://en.m.wikipedia.org/wiki/Lead-cooled_fast_reactor Collateral Damage fucked around with this message at 23:20 on Jan 3, 2018 |
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Jan 3, 2018 18:54
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CommieGIR posted:Its used in space for cooling systems, and was a common refrigerant before CFCs as R717. Naturally, its nasty as all get out and toxic as hell. There was a nonfatal accident involving ammonia coolant on an ISS assembly mission, STS-98. Two astronauts were connecting cooling lines while installing the Destiny Laboratory Module. A defective quick-disconnect valve allowed a bunch of coolant to escape, freezing on the spacesuit of one of the astronauts while he was trying to get the valve closed. His helmet and suit were coated in ammonia crystals an inch thick. Mission Control's advice? Hang out outside for an entire orbit to let the sun evaporate the ammonia off your suit, then run a double-cycle in the airlock. Fill, purge, fill. It took 20 minutes for the life-support system on the station to render the air safe to breathe, so everybody had to wear breathing apparatus.
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Jan 3, 2018 20:35
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Enourmo posted:That's a big "if" though, and aside from mercury most liquid metals necessarily have to operate at very high temps. Iirc there's been research on using them to run nuclear reactors ultra hot (can't have a steam explosion if there's no water) for greater efficiency, but nothing that's made it even as far as the industrial scale prototype phase. It's not just that you can't have a steam explosion, is that you don't have to run your reactor at high pressure to prevent your coolant from boiling away, which is a huge safety benefit, as is the fact that the metal has such a high thermal conductivity that passive cooling in the event of emergency becomes easier. Of course, things like leaks of liquid sodium are kind of a tradeoff. Also, your pumps can be electromagnetic with no moving parts. Also it's really hard to use water as a coolant for a fast reactor because it's such a good neutron moderator, so if you want a fast reactor or a breeder reactor you're pretty much forced into metal coolant. Most of these have been small research plants and the remaining big ones like Superphenix in France have reached their design lives and been shutdown with little interest in building new ones (which is a shame, the IFR would have been loving awesome and liquid fluoride throrium reactors are a great concept), but Russia has a few that are in active service and India's just recently brought one online. A number of submarines have used liquid-metal-cooled reactors. Upside is that you can have very high power densities which is good for cramming a powerful reactor into a tiny hull. Downside is that even when you're tied-up pierside you need to keep the thing warm to prevent the coolant from freezing and utterly ruining the reactor, which is what wound up happening to the Soviet ones (either because they said 'gently caress it, we're decommissioning this boat' and just let it happened or because of accident).
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Jan 3, 2018 22:45
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SPEAKING OF FLUIDS https://www.youtube.com/watch?v=53AcSZ5JDEw My garage lighting is a horrible failure as much as my horribly overfueling CIS is, but you get the idea. Not pictured: that 20L bucket is now full and it only had ~8L in it when I started.
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Jan 4, 2018 07:01
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What is that, a Rx-7? I bet that carries at least a 60 octane rating.
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Jan 4, 2018 07:07
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the spyder posted:What is that, a Rx-7? I bet that carries at least a 60 octane rating. "E21" tells me it's an early BMW 3 series. The mention of "CIS" and google tells me Bosch K-Jetronic Constant Injection System.
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Jan 4, 2018 08:49
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TotalLossBrain posted:The FFTF facility in Washington State was a reactor cooled with liquid sodium. It was used for research and medical isotope production before having its primary cooling loops cut open 10 or so years ago, exposing it to air and permanently disabling it. According to Wikipedia they filled it with argon as the coolant drained so it could theoretically be put back into service.
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Jan 4, 2018 13:49
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Terrible Robot posted:According to Wikipedia they filled it with argon as the coolant drained so it could theoretically be put back into service. That Wiki article is a few years out of date. Decommissioning was completed in 2009.
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Jan 4, 2018 19:29
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Shrugs Not Drugs posted:SPEAKING OF FLUIDS God drat CIS
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Jan 4, 2018 20:23
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Today, I was a horrible mechanical failure. I've been having exhaust problems. My car was loud as hell. I thought I had a hole in the downpipe. I removed the intake and exhaust manifold to make it easier to get to. Turns out there was a chunk of manifold broken off:  Since I don't have another manifold at the moment, I needed to get the car out of the garage and parked to the side of the house. But then I was thinking - do I really need manifolds to run it anyway? My car is on megasquirt, and the fuel rail is attached to the cylinder head. No manifolds required! The MAP sensor is open to the atmosphere, much like the engine would be. I started it up, and naturally it instantly revved up to 9000 and I cut it off. NICE. I got out my laptop and set the rev limiter to fuel cut at 2500 RPM. This worked perfectly, and although it was the loudest thing ever, I could back it out of the garage and park it!  Here's a video of it running with no manifolds: https://www.youtube.com/watch?v=ERUpXMB3T5I
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Jan 7, 2018 00:12
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Running open exhaust ports can More importantly, you really don’t want exhaust gas in the cabin.
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Jan 7, 2018 01:55
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Extra oxygen near your exhaust valves is always bad. It will chip a valve eventually
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Jan 7, 2018 05:48
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Yeah uh I think this was just done to move it to the side of the house, guys.  I don't think 1 minute is going to hurt anything except their eardrums (and possibly relationships with neighbors).That's pretty genius.
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Jan 7, 2018 09:13
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I ran the 914 without exhaust for a minute once. It is indeed the loudest thing ever.
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Jan 7, 2018 12:48
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BloodBag posted:I ran the 914 without exhaust for a minute once. It is indeed the loudest thing ever. I ran the 3SGE in my celica with out a a manifold once. It idled at 2k RPM and sounded like the fabric of time itself being torn asunder, and if you breathed on the gas pedal instead of a roar it was more like a grenade going off. I didn't try to actually rev it, afraid for my (remaining) hearing and slightly worried that the upper ranges might summon Cthulhu.
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Jan 7, 2018 16:31
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Worst I ever did was drive the msp with no exhaust, just open downpipe. Frankly it sounded glorious, you could hear the turbo spool so loudly it echoed.
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Jan 7, 2018 16:45
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Terrible Robot posted:summon Cthulhu. So that's how I wound up on these here forums. 
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Jan 7, 2018 16:46
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The lack of intake manifold is way more awesome than exhaust here, no butterfly, just wide open until spark cut, repeat as needed. It's like having an old WWI airplane rotary where the only throttle was blipping the magnetos on and off.
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Jan 7, 2018 17:13
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 That looks like it hurt.
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Jan 7, 2018 17:53
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Powershift posted:
Somehow this reminds me of: https://www.youtube.com/watch?v=IhI3DJdjSYQ
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Jan 7, 2018 18:06
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Lots of examples of metal and fuel combining and turning into bombs in this video. Bonus gratuitous slow-mo! https://www.youtube.com/watch?v=yCZJinpbGvU
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Jan 8, 2018 20:47
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Magnaflux posted:Lots of examples of metal and fuel combining and turning into bombs in this video. Bonus gratuitous slow-mo! Fuel cars are the most  flavor of Motorsport.
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Jan 8, 2018 21:00
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0toShifty posted:Today, I was a horrible mechanical failure.  And you all thought F&F was full of poo poo. Shame on you.
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Jan 8, 2018 21:10
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Tbf he didn't mention anything about the floor falling off after.
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Jan 8, 2018 22:22
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Magnaflux posted:Lots of examples of metal and fuel combining and turning into bombs in this video. Bonus gratuitous slow-mo! Modern motorsports safety is goddamn nuts. The impacts folks can walk away from are 
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Jan 9, 2018 06:32
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Magnaflux posted:Lots of examples of metal and fuel combining and turning into bombs in this video. Bonus gratuitous slow-mo!
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Jan 9, 2018 18:09
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Magnaflux posted:Lots of examples of metal and fuel combining and turning into bombs in this video. Bonus gratuitous slow-mo! Do the chutes have some automatic trigger if they detect danger to manifold, or does that last driver just have immense reflexes?  Even watching it back and knowing it's going to happen, I don't think I could react in real time to hit the chutes.
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Jan 9, 2018 22:46
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The voiceover seems to say he won the race prior to detonation so he may have pulled them at the finish line, though I don't know a lot about drag racing and it seems like that camera would be at the finish line. I bet they can sort of tell something is wrong long before the whole world catches fire, it's pretty obvious something's not right even at normal speed. Edit: actually I suppose that is like a fraction of a second, upon re-re-watching it no longer looks like something was wrong until right when everything goes all burny. Oddhair fucked around with this message at 23:48 on Jan 9, 2018 |
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Jan 9, 2018 23:44
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I must say the durability of their cages is impressive. Then again I guess they have to be to hold up to a 300 mph worst case crash
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Jan 10, 2018 00:01
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The insane part for me is just how much forged steel and billet aluminium the engine components need to get through to smash everything into a million pieces like they do. And that the superchargers don't end up in the crowd anymore.
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Jan 10, 2018 00:45
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Memento posted:The insane part for me is just how much forged steel and billet aluminium the engine components need to get through to smash everything into a million pieces like they do. And that the superchargers don't end up in the crowd anymore. The commentator points out one that ends up dangling by a thread.
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Jan 10, 2018 19:33
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jammyozzy posted:Do the chutes have some automatic trigger if they detect danger to manifold, or does that last driver just have immense reflexes? There's a burst panel on the manifold that will deploy the chutes when it goes in case something knocks the driver out.
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Jan 11, 2018 04:30
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A red line metro train in Washington DC derailed this morning. https://www.washingtonpost.com/news...m=.caab66de110c
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Jan 16, 2018 03:09
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Thumposaurus posted:A red line metro train in Washington DC derailed this morning. No one injured, thankfully.
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Jan 16, 2018 03:48
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The bigger issue is this is going to keep happening. They invested a ton of money in new trains but oops they weigh more than the old ones and keep loving the track up. A few weeks ago they had to shut a section down for repair for the same issue. This is after a year of a program called "SafeTrack" that was supposed to be fixing these issues and a lot of other deferred maintenance. The metro system in DC is pretty much unusable for me any more it opens too late in the morning for me to use it and on some days closes too early to be effective. I'm not the only one who feels that way. Unless you work a traditional 9-5 schedule it's not really a viable choice for public transportation any more. I just use the bus.
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Jan 16, 2018 13:56
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