Past Activity

Characterization of heat pipes for space applications

Heat pipes are mostly attractive for their special feature to work without movable parts for the process fluid flow. This latter is ensured by the capillarity force provided by the wicks, i.e., a porous medium or ranges, which represents the process driving force. Such featuring makes them very attractive and suitable as heat exchangers for space applications. One of the main drawback consists of the limited heat fluxes which can be removed, around few W/cm2. This is essentially due to the fluid pressure drop in the wicks. The main aim of the research is to ascertain the possibility for the heat pipe (non-gravity assisted) to work with an at least partial extracapillary circulation in the condensing zone. Tests conducted so far have shown that a heat pipe can work with a totally extracapillary circulation in the condenser. This enables the heat pipe to remove a heat flux which is 4-5 times higher (up to 25-30 W/cm2). What is still to be tested is the start-up transient, which is currently in progress. The experimental programme is carried out in the ETCA facility.