Thermal conductivity experiments.

[MustardWarrior]

So I thought I would do some experiments to explore thermal conductivity.  So in the game it says that the heat conduction rate is the lower of the two materials.  I did an experiment with gas pipes that proves that this is not true for gas pipes and I assume it applies to liquid pipes.

https://oxygennotincluded.gamepedia.com/Guide/Heat_Transfer#Thermal_Conductivity

This wiki article says otherwise, but the wiki article is wrong.

Now this does apply to tiles. Basically if you set up a hermetically sealed pair of igneous tiles (the mineral tile not the building) in debug mode that both have 1000kg mass and differ by like 1000 kelvin and also set up an identical hermetically sealed pair, then replace one of the rock tiles with a steel tile at an identical temperature to one it replaced with it's mass adjusted upward to account for it's lower heat capacity (so it would be a mass of 1000kg/0.49) what you will find is that the temperature changes at an identical rate.

If this were true for pipes radiant pipes would be almost useless except for super coolant since nothing has a high enough conductivity to exceed that of the pipe.  However a simple couple of tests shows that this is wrong.

 

For the first test you run hydrogen through pipes that are in a vacuum.  One is a mafic pipe and one is an obsidian pipe.  These two materials have identical specific heat capacity and mass so the only difference is that the obsidian pipe has 2.0 thermal conductivity while the mafic pipe has 1.0 so it makes for a very elegant experiment.  If you do this you will find that the obsidian pipe heats up faster which is in line with it's higher conductivity.  Hydrogen has the lower thermal conductivity but clearly it is not using the lower thermal conductivity as the pipes have heated up by about 70% more.  It is possible that it is using the pipes thermal conductivity number and not some combination because with double thermal conductivity the difference between the two will close faster and since the rate is a linear function of temperature difference you get some curve and not linear temperature change over time.

 

 

For a second test I had a 1000kg pressure 500 kelvin chlorine chamber (I switched to chlorine because hydrogen was heating them up instantly and set up an empty line of mafic gas pipe and an empty obsidian line too. and I think I must have paused and unpaused it for an exact second because the mafic heated up by 80.4 kelvin from it's base 293.2 degrees kelvin while the obsidian heated up by 160.8 so this I think is good evidence that the calculation is using the thermal conductivity numbers of the pipe for the purposes of calculating the heat transfer to the outside.

After doing all of this I found this post where someone decrypted the DLL and then I got that feeling like I was playing checkers while people like him are playing chess. 

 

[FIXBUGFIXBUGFIX]

If you want to make the experiment more precise, focus on temperature change between two ticks (0.2s).

That post is a masterpiece. Though it's old, it still reveals the universe of Klei.

e.g.  No heat transfer between 370 kg water in 300K and 300 kg polluted water in 370K.

[MustardWarrior]

2 minutes ago, R9MX4 said:

If you want to make the experiment more precise, focus on temperature change between two ticks (0.2s).

That post is a masterpiece. Though it's old, it still reveals the universe of Klei.

e.g.  No heat transfer between 370 kg water in 300K and 300 kg polluted water in 370K.

After you posted that I decided to test it and it's true!

Yeah I'm spending more time reading that post and now thermal conductivity is starting to make sense.  The 5x heating for buildings explain why the pipes are instantly heating up and the fact that the conductivity in game says watts when it means kilowatts now makes sense as in 200 kg of igneous rock in contact with another 200kg will start off heating or cooling by about a degree per second as per the conductivity number of 2.0.