Loop Thermosyphons

Two-phase cooling has been utilized in the electronics cooling industry for many decades, with possibly the most well-known adaptation being the heat pipe. Heat pipes are capillary-driven, two-phase devices that rely on the boiling and condensation of a working fluid to transfer heat significant distances with minimal temperature gradient. The flow of the working fluid inside of a heat pipe is facilitated by a capillary wick structure that relies on surface tension to return the condensed liquid to the heat generating components. Heat pipes have found their way into a large number of industries and applications because of their high performance, high reliability, and low cost. Unfortunately, as the electronics industry’s insatiable quest for smaller, higher-powered devices soldiers on, the discrete cooling power of the heat pipe approaches obsolescence.