Imagine you have two identical metal cubes at 0C. One is directly

OP here, I assume it has something to do with the relative densities of the air/fluid and the 100C solid, as well as the total mass of air/fluid, but I don't know how to calculate it.

I guess you have to compare the conductivity of metal with the alpha value (or k) of the forced convection.

Look up the formula for alpha and then solve it for the fluid speed

It's a hard question to answer because there are so many assumptions one would have to make in order to even approximate. Such as the heat capacity of "metal cube", the differential change in the heat capacity as a function of temperature, the effects of friction of moving air, the compressibility of air, the differential rate of heating and cooling meaning that the instantaneous speed of the air must also be differential, I could go on...

If the thread is still up when I get home from work I'll answer. In the mean time, look up 1D conduction, and Forced Convection. I would make the assumption that the airflow hits all 6 sides of the cube for simplicity.

It sounds like OP is trying to get the best cpu cooler.
Just get the evo.

>>8914024
Heatsinks are an entirely different beast than a fucking cube you moron.

Thanks for the good leads nerds

>>8914024
this

>>8914047
They're fancy cubes, is what they are. Sure they have heatpipes and radiator fins, but that's just adding surface are to the cube. You ever held one? They're a goddamn block of metal, and a plain jane cube would make a perfectly fine heat sink, providing it was big enough.

>>8915354
T. Retard

>>8914024
Cryorig H7 > Evo

Is a heatsink topologically a cube?

>>8912571
So the super simple way to do this is to assume the 0C and 100C cubes have the same mass and heat capacity and are isolated, such that they equilibrate to 50C. Then you can use the relation Q = mC∆T to find the heat transferred to heat the 0C block to 50C. Then you can use the different heat capacity of air to find the mass of air at 100C needed to heat the 0C block to 50C. You can use other assumptions to find the necessary mass flow rate, and therefore fan speed.

The more accurate way to do this is to use differential equations modeling heat conduction. You can find them in any transport phenomenon book. They're pretty simple to solve if you make the geometry easy on yourself. Generally what you're looking to do is equate the heat flux from the cube to the heat flux of the air.

if literally anyone ever took heat transfer, you'd know its a very simple question, as long as you know the type of material/properties of the objects

http://www.sfu.ca/~mbahrami/ENSC%20388/Notes/Forced%20Convection.pdf

>>8915546
hint:

lumped capacitance

https://www.et.byu.edu/~vps/ME340/TABLES/5.1.pdf

>>8915530
>Then you can use the different heat capacity of air to find the mass of air at 100C needed to heat the 0C block to 50C.
it wont reach an equilibrium at 50C, the air will continue to heat until 100C

>>8915530
What makes you think the hot cube isn't generating heat?