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insulated tiles don't insulate liquids


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i can't stabilize my liquid hydrogen production.

problem seems to be that the insulated tiles (insulation) don't really insulate when they touch liquids.

the following setup just evaporated a filled and cooled tank of liquid hydrogen

image.thumb.png.26418db969b85c1dc2a2cf1826f727f1.png

all insulated tiles touching liquids change temperature.

any advice is welcome

regards

McCriddle

P.S.: there are no tempshift plates in this setup

 

 

 

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Use metal tiles to contain the hydrogen, then surround the metal tiles with insulated tiles or vacuum. Metal tiles will stabilize at the correct temperature very fast, and insulated tile /solid tile heat transfer can be considered zero in most cases. 

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i know i could rebuild... and then insulate everything with vacuum chambers.

just wanted to check if the setup is wrong

so insulated tiles don't work for liquids, right?

changing temperature by almost 300° within ~50 cycles for insulated tiles made of insulation doesn't really help 

 

 

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When an insulated tile is touching gas on one side it will transfer heat much faster than normal. You can see it while containing magma: the tiles touching magma won't change temperature much if you leave vacuum in the chamber.. But if you leave gas inside, it will superheat and the tiles will heat up to magma levels. I haven't tinkered with insulation enough to know for sure if this mechanic applies to it, but since it has NOT ZERO thermal conductivity, and since I see steam above the tank, and you say it was full.. I guess it's what happened. If there was vacuum there, they would drift towards the temperature of the hydrogen.

As an experiment, try to cool down those tiles, running lead radiant pipes inside them.

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can't say anything about flaking...
 

26 minutes ago, 6Havok9 said:

When an insulated tile is touching gas on one side, it will transfer heat much faster than normal. You can see it while containing magma: the tiles touching magma won't change temperature if you leave vacuum in the chamber.. But if you leave gas inside, it will superheat and the tiles will heat up. I haven't tinkered with insulation enough to know for sure if this mechanic applies to it, but since I see oxygen (I suppose at room temperature) above the tank and you say it was full.. I guess it's what happened. If there was vacuum there, they would drift towards the temperature of the hydrogen.

no room temperature... steam chamber above with isnulated tiles in between (those stay at 40°C since i buld them) and the two cooling chambers at -217°C/~-255°C right now ... with the oxygen chamber beeing at the same temperature as the cooling loop and the hydrogen chamber ~3-4°C above the loop and beeing instable.

and the whole setup surrounded by vacuum

 

the top insulated tiles between the two chambers which didn't touch any liquid but just the gases are still at 40°C as well



how does flaking occur in ONI?

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23 minutes ago, OxCD said:

Couldn't it be due to flaking ? As far as I recall, TC isn't involved into heat transfer mecanisms when this happened.

That's exactly what I was trying to say, but well, words :wilsondisapproving:  Though it's probably partial evaporation.

Insulated tile touches steam. And liquid hydrogen. Insulated tile heats up and, upon reaching a high enough temperature delta between tile and hydrogen, causes a bit of hydrogen to evaporate. You can see this when liquids touch hot abyssalite. Becomes a runaway process, unless you:

-remove the heat source touching those tiles or

-cool down those tiles or

-brute force it and overwhelm the partial evaporation until tiles drift towards a temperature that doesn't allow It to happen.

I wish I could write like a normal person. :-(

I noticed It was steam only after zooming in. Soz about that. Insulation has a TC so low that room temperature oxygen would probably not allow this thing to happen. But steam is continuously reheated, and at much higher temperature than 40°c. So some transfer should happen.

 

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hmmm... so sounds to me like the only reliable way to insulate is vacuum then, right?

if so: is there any advantage to use insulated tiles over normal tiles?

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7 minutes ago, McCriddle said:

how does flaking occur in ONI?

The wiki has a pretty good page on it:

https://oxygennotincluded.fandom.com/wiki/Flaking

The basic criteria are that

  • the liquid cell is above 5kg
  • the liquid cell is more than 3C below it's evaporation temperature
  • the solid cell is more than 3C above the liquid's evaporation temperature.

If those are met, heat will be drained form the solid cell to convert 5kg of the liquid into a gas.  Crucially this effect completely ignores thermal conductivity, and will even happen with insulated insulation (as you found the hard way). If you wait long enough, this will cool the insulated tile down enough until criteria 3 is no longer fulfilled.

Since there's no way to avoid it, the usual advice is to line the liquid chamber with low SHC metal tiles (gold), since they will much more quickly equilibrate and the flaking will stop. Then use insulation around metal tiles to isolate the chamber.

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10 minutes ago, McCriddle said:

if so: is there any advantage to use insulated tiles over normal tiles?

Yes, if you don't want to keep the contraption surrounded by vacuum. Insulated tiles transfer heat extremely poorly to other solid tiles.

If you want to keep this same build you could run pipes inside the problematic insulated tiles. 

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ahh.... slowly getting some light into this.

 

do i understand correctly that flaking doesn't apply to condensation?
meaning in my build i should be mostly fine when the insulation tiles hit a temperature lower than -249.2°C. (mostly because without flaking the temperature of the insulated tiles won't change in a relevant speed)

and i could expand my hydrogen cooling loop into those tiles to minimze these chances even more?

 

just noticed... those insulated tiles on all sides of those liquid chambers now are exactly at evaporation temperature - 3°C

thanks alot guys :cheerful:

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5 hours ago, McCriddle said:

image.thumb.png.26418db969b85c1dc2a2cf1826f727f1.png

What material did you make all insulated tiles?  I see the highlighted ones have insulation but in the material overlay picture shows they have a different color 

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3 hours ago, McCriddle said:

do i understand correctly that flaking doesn't apply to condensation?

It does not. Flaking can only phase change up, not down.

3 hours ago, McCriddle said:

meaning in my build i should be mostly fine when the insulation tiles hit a temperature lower than -249.2°C. (mostly because without flaking the temperature of the insulated tiles won't change in a relevant speed)

Yes, indeed. That's why it's recommended to minimize the thermal mass for a faster start-up in LOX/LH builds.

3 hours ago, McCriddle said:

and i could expand my hydrogen cooling loop into those tiles to minimze these chances even more?

Not really in this case, since they are insulated insulation tiles with a Thermal Conductivity of 0.

Anyway, the limiting factor is always going to be the cooling ability of your build vs the thermal mass to be cooled down, it doesn't really matter if you cool the hydrogen directly or the tiles around it, both will need to reach hydrogen condensation point.

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On 3/8/2022 at 6:59 AM, McCriddle said:

i can't stabilize my liquid hydrogen production.

problem seems to be that the insulated tiles (insulation) don't really insulate when they touch liquids.

the following setup just evaporated a filled and cooled tank of liquid hydrogen

image.thumb.png.26418db969b85c1dc2a2cf1826f727f1.png

all insulated tiles touching liquids change temperature.

any advice is welcome

regards

McCriddle

P.S.: there are no tempshift plates in this setup

 

 

 

It seems no one is talking about the locked door on the right side of the liquid hydrogen chamber. Is it just as simple as you have an excellent thermal conduction "hole" in your insulated wall?

Liquid O2 has a broader temp range so you maybe don't notice it as much on the left chamber, but liquid h2 has a super narrow range and it's very easy to boil it.  You may just be allowing a bit of environment heat to conduct in.

 

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On 3/8/2022 at 4:45 PM, McCriddle said:

hmmm... so sounds to me like the only reliable way to insulate is vacuum then, right?

if so: is there any advantage to use insulated tiles over normal tiles?

No and yes/no.

Under certain conditions there is actually zero heat transfer between insulated tiles and other tiles. I go into it in this post: 


So for example a Ceramic Insulated Tile which is at room temperature, will only exchange with a low mass solid or liquid tile if the temperature difference is at least ~670 C, or with a gas tile if the temperature difference is at least ~37 C (these numbers get bigger if the heat capacity of the other tile exceeds the heat capacity of the ceramic insulated tile, like for a 1840 kg magma tile the temperature difference required for heat transfer into an insulated tile is like 3000 C, the magma would be rock gas). An Insulation Insulated tile will never exchange heat with solid or gas tiles via simple conduction, but can exchange heat via partial evaporation which bypasses conductivity.

However partial evaporation can not occur between solid tiles, so if you have a Lead Metal Tile which is at say -263 C, next to a Ceramic Insulated Tile at 20 C, there will be actually zero heat transfer between them: with no vacuum required.

Double-walling with one of the walls being Insulated Tiles can be extremely useful for creating zero heat transfer without needing a vacuum. However in the case where actually zero heat transfer can be achieved there is little benefit in making both walls out of insulated tiles, indeed double insulated tiles offers no advantage in terms of achieving zero heat transfer, though in the case where actually zero heat transfer is unattainable (for example a hot gas with materials lesser than Insulation) then double walling with insulated+normal will reduce heat transfer by 25x since gas conducts heat into an insulated tile 25x faster than solid/liquid does, but double walling with both tiles being insulated will decrease heat bleeding through the walls even more than that, but is probably overkill as an inner normal tile and outer insulated tile is already very good insulation.

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