Heat exchange - What with What?

[Olleus]

I'm trying to figure out how heat exchange works in this game, I've got most of the pieces in my head, but I still have some gaps. This https://oxygennotincluded.gamepedia.com/Thermal_Conductivity is very useful, but not so clear to me. The formulas are fine, but I don't understand the scenarios, in the order they are listed on the wiki:

1) Cell to Cell. I imagine this is any solid/liquid/gas tile exchanging heat with any of it's neighbours. Vacuum tiles ignore this I guess? Neighbours don't include diagonals?

2) Entity inside of a cell to the cell. I don't get this. Does it mean things like debris and the gas/liquid cell that the debris is in? What else counts as an entity rather than a building?

3) Debris and the solid cell it is on top of. This is fine, although I don't really understand the difference between this and the one above.

4) Building and the cells it occupies. This is clear to me I think, although I'm not entirely sure what counts as a building, do Drywalls and Tempshift count? What about pipes or wires? Does the building share heat with every cell it occupies, or just some?

5+6) (Insulated) pipes and their content. Also clear to me. Conveyor belts count as pipes for this?

 

If I understand this correctly, there is no direct heat transfer between buildings on the same tile or adjacent tiles. So if I have two (radiant) pipes next to each other and I want to transfer heat between them, the heat flows as:

content of pipe 1 -> pipe 1 -> cell 1 -> cell 2 -> pipe 2 -> content of pipe 2

so I'll get a faster heat flow if I fill cell 1 and cell 2 with a liquid with high conductivity rather than with gas. Am I right that if cell 1 and cell 2 are vacuum, the pipes will *never* exchange heat? What if I put tempshift plates behind cell 1 (or behind both cells)?

 

My second major question is what happens to the contents of a building. Do the various things inside of a storage bin exchange heat with each other? With the building itself? With the cells the building occupies?

 

As an aside, I find it super weird that I can't radiate heat out into space. I get that the game only models conductive heat transfer, but this is so counter intuitive to me. If you're stuck on an asteroid, radiating heat into space is literally your *only* real solution, rather than all the crazy thermodynamic breaking machines in the game. Does this mean I have to cool my space biome bunker doors before they eventually melt?

[Yoma_Nosme]

20 hours ago, Olleus said:

Am I right that if cell 1 and cell 2 are vacuum, the pipes will *never* exchange heat? What if I put tempshift plates behind cell 1 (or behind both cells)?

Pipes won't exchange heat in vacuum. With tempshift neither.

You need a transfer medium as you said...

Tempshift exchange heat to surrounding gas, tile, or liquid..(or tempshift - wrong)

Liquid and gas storage exchange heat with the tile below. Gas storage with the *2nd from left*(not 100% sure which one)

20 hours ago, Olleus said:

Do the various things inside of a storage bin exchange heat with each other? With the building itself? With the cells the building occupies?

They exchange heat with the surrounding medium for sure.

not too sure if the material they're made of has importance -don't think so -

I don't think materials inside exchange directly either because  there be builds around just filling compactors with material you want to cool or heat and ice or igneous rock for example and done, boiler/cooler for free

[Gurgel]

Here is my incomplete and possibly flawed take on things:

1) Yes. Vacuum tiles do not ignore this, they just have zero thermal conductivity and count as insulated, at lest I assume that is the implementation. Diagonals are not included.

2) Dupes and critters. Nothing else, I think.

3) Debris is not an entity AFAIK

4) There are a lot of special cases here. For example many (most?) buildings have one or several "contact tiles" and do not exchange heat with their surroundings anywhere else. I think wires may be treated the same as non-insulated pipes and it seems there is no transfer wire-segment to wire-segment. Same for pipes, I think.

5/6) Conveyor belts are special. They do not seem to exchange heat at all with what they transport, unlike pipes. What a conveyor belt transports does exchange heat with the surroundings, but I am unsure of the factors involved.

[Olleus]

Ok, this mostly makes sense to me. So debris heats up the tile underneath it, but not the cell it's on? Strange but, fine.

 

I'm trying to cool down my space biome environment. Currently I have a diamond floor layer with a radiant pipe filled with cooled oil flowing through it , and an insulated tile layer below it. This is working very well to keep my space buildings at a reasonable temperature and preventing any thermal fluctuations in my habitat below it. HOWEVER, I have an Auto-Sweeper in space, vertically on the floor, that is not getting cooled at all. Adding tempshift plates behind it didn't help. I guess the only cell of the Auto-Sweeper that matters for heat transport is the central one, and in my set up it isn't touching anything, so it heats up while hoovering asteroid dust but never cools. How do I solve this?

[Gurgel]

10 minutes ago, Olleus said:

HOWEVER, I have an Auto-Sweeper in space, vertically on the floor, that is not getting cooled at all. 

Auto-Sweepers do not have a contact tile. When you look at them, this makes kind of sense as they are not standing on anything. What you need to do is put one of their tiles in some liquid or gas. I usually place a solid tile under, drywall behind and then drip 5g/s or so of water on that tile:

The same works horizontally. You need to only cool them in one place. The tile you place below does not need to be insulated but does not need to be cooled either. The water already does that.

Some people do something similar with gas and cool the tile instead of the gas. The Gas only acts as contact medium in that case and 1g/s of any gas seems to work fine.

[Olleus]

1 minute ago, Gurgel said:

Auto-Sweepers do not have a contact tile. When you look at them, this makes kind of sense as they are not standing on anything. What you need to do is put one of their tiles in some liquid or gas. I usually place a solid tile under, drywall behind and then drip 5g/s or so of water on that tile:

The same works horizontally. You need to only cool them in one place. The tile does not need to be insulated.

Urg, that really sucks. Dripping is annoying, specially as I have it working in tandem with a sweepy to keep my floor free of meteorite droppings. If I drop petroleum slowly it won't get hot enough to evaporate and I'll end up with tons of bottles created by sweepy that I have no use for. Is there a more elegant solution?

[Gurgel]

9 minutes ago, Olleus said:

Urg, that really sucks. Dripping is annoying, specially as I have it working in tandem with a sweepy to keep my floor free of meteorite droppings. If I drop petroleum slowly it won't get hot enough to evaporate and I'll end up with tons of bottles created by sweepy that I have no use for. Is there a more elegant solution?

Use the gas solution, as your floor is already cooled. Just put a drywall and blow 1g/s of gas on the Auto Sweeper. That should establish thermal contact to a neighboring tile. It should also establish contact to a Temp Shift plate if needed. I think you can even make longer thermal chains by alternating Temp Shift and normal tiles in Vacuum as that exchange should work directly.

[psusi]

5 hours ago, Yoma_Nosme said:

Tempshift exchange heat to surrounding gas, tile, or liquid..or tempshift 

Nope; tempshift plates exchange heat with the gas/liquid/solid in the surrounding 8 tiles.  They never exchange heat directly with other tempshift plates.

[OxCD]

9 hours ago, Olleus said:

Is there a more elegant solution?

You can use this layout I've made. Petroleum is standing over the glass tiles, and not moving. Radiant pipes with fresh pH2O flowing into. No dripping, steel only (with 125° overheat temp, they will overheat sometimes, briefly, but it could take a lot of time to burn completely, and of course if you have dedicated AT+turbine combo).

100% coverage for miner and conveyor system. Just be careful where you stop the "blueprint". If I remember correctly when I built this, you should stop it on the conveyor (or the left or right tile, it should work too) if you wanna keep the 100%.

[Yalp]

8 hours ago, OxCD said:

they will overheat sometimes

Probably due to regolith getting into contact with the petroleum puddles. If the bottom row of Mesh Tiles were put one tile higher they wouldn't get into contact. Miners should still be able to cover the whole area.
Obviously it will impact dupe travel time. But since everything is automated, there shouldn't be a lot of dupe traffic up there if any at all.
It might not look as clean as it does as shown in the picture.

Another measure could be to replace the 'outer' glas tiles (2. picture) with mesh, removing the petroleum, preventing contact. This also gives a (very little) extra light down below.

[Badpip]

Cooling in vaccum is an annoyance, i just put open doors on top of mesh tile to get rid of regolith until i have space material to don't worry about robominer and autosweeper overheat because regolith and use the regolith as "coolant", it's a little exploity but it's just qol for me cooling in vaccum dont change difficulty it make just things annoying.

[BaZERGer]

Maybe it's possible to cool the regolith enough to be steel safe before it drops down, if you don't have space material. Running several rows of pipes on top of the bunker door to a Steam Turbine.

Although the liquids that are safe for that temperature without Super Coolant aren't as effective carriers..

[OxCD]

3 hours ago, BaZERGer said:

Maybe it's possible to cool the regolith enough to be steel safe before it drops down, if you don't have space material. Running several rows of pipes on top of the bunker door to a Steam Turbine.

Although the liquids that are safe for that temperature without Super Coolant aren't as effective carriers..

Even with my setup above, the 300°C regolith is mined well before steel machines overheat. 125°C overheating machines (gold, iron, etc...) can also do the job for hundred of cycles before to be completely burned. And this only with pH2O (supercoolant can improve later). There's no point I think to try to cool the regolith on top of bunker coverage. You'll destroy a lot of heat, while freshly mined rego keeps its 300°C, so you'll be able to use it in a steam chamber to power a turbine, for example.

13 hours ago, Yalp said:

Probably due to regolith getting into contact with the petroleum puddles.

Yep I know, no doubt about that. But as said, 125°C overheating machines can keep up for a long time before to be burned. So you'll have plenty of time to refine your steel, if you want to get rid of the overheating completely.