Current Heat Transfer Mechanics

[caffeinated21]

Question on current heat transfer mechanics. The *classic* Yothieo post above mentions using the lower of the two materials conductivity for heat transfers, but I swear I’ve heard that this has been changed to some kind of average (log average?)

I’m particularly interested in an item on conveyer rail transferring to the tile it’s moving through. I think this is an entity by the terminology in the above post...

[Coolthulhu]

Yes, it's log average now, at least in the most common case. Not all tooltips have been updated, some still mention the old minimum.

I'm not sure if an item on conveyor transfers directly to environment or to the rail, but that should be trivial to check. Once you know that, it's just the same deal as with all other heat transfers.

[DaveSatx]

53 minutes ago, Coolthulhu said:

Yes, it's log average now, at least in the most common case. Not all tooltips have been updated, some still mention the old minimum.

I'm not sure if an item on conveyor transfers directly to environment or to the rail, but that should be trivial to check. Once you know that, it's just the same deal as with all other heat transfers.

i remember the patch that said it was changing.. then they reverted it.. did they re-re-vert?

[Z0366]

2 hours ago, Coolthulhu said:

Yes, it's log average now, at least in the most common case. Not all tooltips have been updated, some still mention the old minimum.

I'm not sure if an item on conveyor transfers directly to environment or to the rail, but that should be trivial to check. Once you know that, it's just the same deal as with all other heat transfers.

Can I please learn a little more about the log average?

is it

log k_true=log k_material1+log k_material 2?

[qda]

k_eq  = k_2 - k_1 / (log(k_2) - log(k_1)) (neper logarithms ofc)

I'm not sure about the equivalent thermal conductivity though, if I had to guess, I would bet on a geometric mean k_eq=sqrt(k_1*k_2), since it is closer to min(k_1,k_2) when conductivities are very different, which is the feeling I get when playing (i.e geometric mean is always < logarithmic mean)

[Angpaur]

17 hours ago, Coolthulhu said:

Yes, it's log average now,

Average conductivity is used only in case of regular/radiant pipes exchanging heat with its contents. And for me it is still unclear if it is log or just simple average.

For almost all other cases a lower conductivity is used.

[Coolthulhu]

1 hour ago, Angpaur said:

Average conductivity is used only in case of regular/radiant pipes exchanging heat with its contents.

Any sources on that?

I tried DotPeeking the assembly, but it seems that all important thermal calculation is done in binaries nowadays.

The only kind of transfer I've seen that still uses minimum conductivity is one involving creatures.

I'm pretty sure that pipe/surroundings transfer is not minimum. Changing pipe material to thermium noticeably enhances it, even though all metals have higher conductivity than any possible surroundings.

[Angpaur]

42 minutes ago, Coolthulhu said:

Any sources on that?

 

[hackcasual]

Items on conveyors seems to transfer heat very quickly with tiles they go through at least. Insulation doesn't seem to matter.