Heatpipe placement question

[angrypig7]

I know that heatpipes work by filling up low pressure gases like acetone so when it evaporates, the hot air goes up to heatsink fins and cool liquid gets down

to the source of heat like CPUs and GPUs. If I'm right, shouldn't heatpipes only be placed vertically and the source of heat should be lowers that the heatsink fins??

Because CPU heatsinks tend to place heatpipes horizontally, and GPU coolers usually have the fins lower than the GPU. How do heatpipes in theses cases work??

[19_blackie_73]

heatpipes are most times a solid piece of copper. the technique you are referring to is vapor chamber design and in this case it matters afaik.

the principle of solid heatpipes is that you use a material which has good thermal conductivity (equal low resistance in cables for current) and this way you can transport heat away from the place the heat appears.

[TheRandomness]

1 minute ago, 19_blackie_73 said:

heatpipes are most times a solid piece of copper. the technique you are referring to is vapor chamber design and in this case it matters afaik.

the principle of solid heatpipes is that you use a material which has good thermal conductivity (equal low resistance in cables for current) and this way you can transport heat away from the place the heat appears.

Heat pipes are hollow. Vapour chambers are just flat heat pipes. 

[angrypig7]

6 minutes ago, 19_blackie_73 said:

heatpipes are most times a solid piece of copper. the technique you are referring to is vapor chamber design and in this case it matters afaik.

the principle of solid heatpipes is that you use a material which has good thermal conductivity (equal low resistance in cables for current) and this way you can transport heat away from the place the heat appears.

Oh, as far as I know, that is not a heatpipe.(I just google it to make sure)

And most of the GPU and CPU heatsinks have heatpipes not copper bars.

[WoodenMarker]

Wicks.

http://www.aavid.com/product-group/heatpipe/operate

[nycesquire]

On 7/6/2016 at 7:30 AM, angrypig7 said:

[nycesquire]

You're generally correct. Heat pipes work best when the cool side is above the hot side.  That's known as gravity-assisted flow.  The working liquid evaporates  at the hot end, rising up to the cool end.  It condenses, and then flows back down to the warm end.  Heat pipes will work even without gravity assistance, though, because they have wicks. Still, they work more efficiently in the orientation you describe.  I'm using heat pipes in my project (linked in sig).

[angrypig7]

Thanks for the reply. This is the kind of answer I've been waiting for