# Test format idea to assist in finding the heat transfer equations for many objects.

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If I have a practically infinite heat sink, and a practically infinite cold sink; horizontally apart from each other, and I place a 1 high 'conductive' band (by conductive I mean greater than zero conductivity) between them; then eventually over a long period of time, there should be a constant heat flow through the 'conductive' band; and evenly through the entire band. The heat into any object, should be equal to the heat leaving the object, for every object in the conductive band. An "object" can be any medium (whether it be gas, liquid, or solid), or a building with sufficient area to connect two mediums (IE a tempshift plate). Buildings can only transfer with mediums and not other buildings, so keep that in mind.

By measuring the dT (difference in temperature) needed between two objects to meet the heat transfer constant of the conductive band; you can get an idea of the heat formula. Two objects that transfer heat well through each other, should have a low dT between them. Two objects that transfer heat poorly through each other, should have a higher dT between them in order to get the same heat transfer. I denote the heat transfer coefficient to be Z, which is = (heat transfer between two objects/dT).

While Z is strongly correlated to conductivity, it will also show you any other multiplication factors included in heat transfer, and will show you whether it considers the conductivity of both objects or just one, and how it uses them in the formula.

Z only exist for two objects interacting. So granite tile doesn't have a Z value; but Granite tile-Granite tile does have a Z value, and Granite tile-igneous tile has a Z value. Z values might also depend on order for some object combinations. So object 1- object 2 might have a different Z value than object 2 - object 1. I denote the hotter object as the one on the left, so the left object is the one putting heat into the right object.

Z values for a specific order of two objects, should always be the same. If this isn't true, either there is something different between the two objects this time, or the test was done wrong, or the entire premise of these types of test is wrong.

Since heat transfer between 2 objects can be hard to measure, therefor it can be difficult to get an exact value of Z; it will be better to denote a Z value ratio relationship to another Z value rather than its raw number. Since other object combinations in the band should have identical heat transfer; you should be able to calculate the Z ratio fairly easily.

Example: I measure the dT between object 1 and object 2; and between object 3 and object 4; all of which are in the same conductive band after it has stabilized. The dT of object 1-object 2 is double that of the dT of object 3-object 4.

Since I know they have the same heat transfer between them; the Z value of object 3-object 4 is double that of the Z value of object 1-object 2. To put it in formula form. (dT1,2)/(dT3,4)= (Z3,4)/(Z1,2). (preferably I'd be using subscripts to denote the different dT and Z values). So really this is an experiment for finding Z value ratios.

Failure condition: This experiment assumes that heat sinks are practically infinite, IE they don't change much temperature over the experiment and have far higher thermal mass than the entire thermal band (well over 100 times the thermal mass of the conductive band). If they aren't practically infinite for the purposes of the experiment, then the heat transfer through the system will be changing a lot over time, which can interfere with getting good Z ratio measurements.

The experiment also has to run long enough that the temperature of the each part of the conductive band stabilizes. If it doesn't stabilize, that means the heat in =/= the heat out; which will prevent measuring accurate Z values.

Other failure condition can include variation with the heat sinks. Some heat sinks might have their own internal factors that can change the heat transfer to and from them, which can interfere with measurement results. Make sure you look at the temperature over the heatsinks themselves, and the temperature of the parts of the conductive band in direct contact. In theory, any minute change in temperature in the heat sinks should be near equivalent for both if they have the same thermal mass and significantly higher thermal masses than the conductive band. In addition, assuming heat transfer coefficient between them and the part of the conductive band they are touching is equivalent, there should be an equivalent temp difference between each heat sink and the part of the conductive band they are touching.

Other way to notice a failure condition is if you are getting different Z ratios for things that should be the same. This can denote that heat transfer through the system didn't stabilize yet, or it could show that this entire test is bunk.

Hopefully the premise of these types of test isn't bunk.  What are your thoughts and criticisms of this?
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So you want to find heat transfer equations?

Well, you are too late. It is already found:

But do not despair!

Some part of it might be outdated and for example seems like klow is no longer used in tile to tile equations, except for insulated tiles. So there is still room for testing and verifying already found knowledge.

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47 minutes ago, Angpaur said:

But do not despair!

Some part of it might be outdated and for example seems like klow is no longer used in tile to tile equations, except for insulated tiles. So there is still room for testing and verifying already found knowledge.

I actually went through both of these post before, and wanted a way to find out what was still accurate since both post are from pre-launch.  And there seems to be somethings that are different now.

I probably should have referenced these forums in my post though, to avoid people linking them to me as a reply.  My bad.