Heat Pipe Heat Exchanger

Description

A heat pipe is a heat-transfer device that employs phase transition to transfer heat between two solid interfaces. At the hot interface of a heat pipe, a volatile liquid in contact with a thermally conductive solid surface turns into a vapor by absorbing heat from that surface. The vapor then travels along the heat pipe to the cold interface and condenses back into a liquid, releasing the latent heat. The liquid then returns to the hot interface through either capillary action, centrifugal force, or gravity and the cycle repeats.

Due to the very high heat transfer coefficients for boiling and condensation, heat pipes are highly effective thermal conductors. The effective thermal conductivity varies with heat pipe length, and can approach 100 kW/(m⋅K) for long heat pipes, in comparison with approximately 0.4 kW/(m⋅K) for copper.

The most important feature of heat pipe heat exchangers is that they are very suitable for gas-to-gas heat transfer with medium temperature between 300°C (572°F) to 50°C (121°F).

The super thermal conductivity property inside the heat pipe makes it possible to add fins on each interface respectively. With enhanced heat transfer surfaces on both the hot and cold sides, the heat pipe heat exchangers have higher heat transfer efficiency and minimal resistance losses on both interfaces, such characteristic that makes it well suited for low temperature gaseous heat recovery.