Using doors for heat exchange, but not that way

[occamrazor 28]

Been fooling around with heat exchangers to get an optimal build. Read one of the heat transfer threads this morning (don't remember which one) and it mentioned that doors are better for HEx because they're a single building (not two tiles). Found some time to test that out and yep doors outperform tiles as a heat transfer medium.

Neat trick.

This is a flawed experiment. Ignore

 

LtR: Pneumatic door, manual airlock, mechanized airlock, diamond window tiles. Door material is aluminum ore. Pipes are Al. Polluted water starts at 110° and -19° C. Transferred 5t.

Cold output results:

Mechanized airlock: 6.7° C

Diamond tile: 7.4° C

Manual airlock: 8.2° C

Pneumatic door: 106.8° C

Hot output results:

Mechanized airlock: 70.3° C

Diamond tile: 77.6° C

Manual airlock: 74.2° C

Pneumatic door: -17.6° C

Edited November 9, 2020 by occamrazor

[Gurgel 2063]

That is a really interesting observation!

Edited November 7, 2020 by Gurgel

[blakemw 48]

Doors actually are two tiles, but the door object only shows the temperature for the left or bottom tile (and when the door is opened, the tiles are deleted and the temperature is averaged, and when it's closed the tiles are created at the same temperature, but can then diverge). It is straightforward to demonstrate that doors have two tiles which can have different temperatures. Make a door, and build a one tile object inside each tile of the door (i.e. an automation wire, or whatever, anything really), put heat across the door so there should be a gradient (i.e. one side hot, the other side cold), and check the temperature of each object. It can be observed that they have different temperatures, hence the different tiles of a door do have different temperatures.

And an even simpler way, is to just click twice on each side of the door, so you see the underlying tile, and it will have its own temperature under the properties tab.

I am not doubting that in some cases doors make better heat exchangers, but if so it's probably 100% due to them having different material properties, i.e. a Mechanical Airlock consists of 2 200 kg Tiles, wheras a Metal Tile is a 100 kg Tile, and higher mass (heat capacity) can make for more effective heat exchange. You can also verify this hypothesis by using Sandbox Mode brush tool to compare a Steel Mechanical Airlock with a pair of 200 kg natural tiles made of Steel, they should be precisely identical in performance. Or you could compare the performance of a Manual Airlock, with a pair of Hydroponic Tiles of the same material.

edit: These rules don't apply to Pneumatic Doors or open Airlocks. I don't know what rules apply to Pneumatic doors, but they act neither like tiles nor buildings, having somewhat slower heat exchange than comparable buildings and much slower than tiles.

Edited November 7, 2020 by blakemw

[wachunga 448]

Looking at the results shows that there is a problem with the test. Consider the changes in temperature of the mech door setup. Hot went from 110C to 6.7C, a loss of 103.3C. Cold went from -19C to 70.3C, a gain of only 89.3C. 14C worth of heat is missing, where did it go? It went into the testing apparatus, bringing it towards it's steady state operating temperature. Problematically, the reservoir is storing liquid from the beginning when a lot of heat was being lost to the apparatus. Any results taken from those reservoir temperatures are invalid. Furthermore the thermal mass of each test is different, diamond has the least then manual then mech. This shows in the results, diamond is missing the least amount of heat then manual then mech.

To run this test properly, get rid of the reservoirs and just dump the water out somewhere. Let the test go for several cycles until you reach the steady state operating temperature. Then take your temps from each output pipe. In such a test, manual and mech are virtually identical. As @blakemwsaid heat capacity can have an effect, but in this particular case the difference between the doors is not meaningful. However, the diamond is indeed a couple degrees better than the doors.

@occamrazorPlease don't take this as deflating criticism. Most people are too lazy to even bother with any sort of testing at all, so kudos to you for putting in the effort. If you find this sort of thing mentally engaging, check out the wiki page on conductivity. It has a lot of good information about the rather unintuitive mechanics.

Edited November 8, 2020 by wachunga

[Glassyfo 240]

Why are you comparing metal doors to diamond tiles? Shouldn't the elements remain constant if the building type is the variable? It should be metal aluminum tiles should it not?

Edited November 8, 2020 by Glassyfo

[occamrazor 28]

On 11/8/2020 at 1:41 AM, wachunga said:

@occamrazorPlease don't take this as deflating criticism. Most people are too lazy to even bother with any sort of testing at all, so kudos to you for putting in the effort.

Thanks. I thought something was a little fishy.

[psusi 307]

I can't figure out what your numbers mean or where you measured them.  Looking at the picture, it appears to me that the pneumatic doors transfer no heat ( expected ), and the other 3 appear to be pretty much the same.  The heat transfer is probably being limited by the pipe rather than aluminum vs diamond.