[Althornin]

Originally Posted by Long Haired Git

Maybe we'll get a clarification.

I don't see any difference between a heatpipe and how AngryAlpaca thinks this works. The amount of SA at the condensor, and number of thermal interfaces at the condensor, are merely implementation compromises of commercial heatpipe waterblocks. The "home made" heatpipe (already linked within this thread) did away with the latter. Anyway, if the sole means of heat transfer is the evap/condense (bubbles), then its a heat pipe. Given two parallel paths, and returning of liquid via the same path, I can't see how any real coolant "flow" would be created, and the cooling of any flow would be immaterial compared to the cooling by the bubbles. So its a heat pipe.
Given this, then one large tube would be probably better, and yes AngryAlpaca's comments on the waterblock apply.

But I don't think its a heat pipe.

I think its a "syphon" as described. I think , as per a posting above, the bubbles contribute to fluid flow in that they go up one tube only, and hence there is a real "flow" eventually established. Not exactly a high flow rate, but flow none-the-less. This flow allows "normal watercooling" to contribute significantly to the overall efficiency of the rig.

However, UNDERBYTE's comments on condensor/evaporator design still apply, so I'll shut up now.

Well, in the article, there is a link to an article on thermosyphons, where the following is said:

The thermosyphon involves four
components in a loop: an evaporator with a boiling enhancement structure, a rising tube, a condenser
and a falling tube.

It also says this:

A thermosyphon is such a device, which successfully implements two-phase liquid cooling by
indirect contact with electronics. A two-phase thermosyphon basically consists of an evaporator
and a condenser, which are connected through a passage, or a loop. Heat is transferred from the
source through an interface to the evaporator, where the fluid vaporizes taking the latent heat of
vaporization. The vapor then moves to the condenser, where it condenses. The released heat is dissipated
to the ambie nt from the condenser and the condensed liquid is returned to the evaporator,
thus completing a closed loop

So, what it is describing is a heatpipe - there is no "liquid flow", but a cycle.