Heat pipes with self-rewetting fluids under low-gravity conditions

The work presents experimental tests about the performance of heat pipes filled with a “self-rewetting“ fluid (alcohol aqueous solutions). Comparison with conventional commercial water heat pipes is also considered. The used fluid exhibits an anomalous increase in the surface tension with increasing temperature. Along these lines, the fluid has been investigated as a possible means to improve heat transfer inside the heat pipes with a focus, in particular, on space applications (next generation satellites). The experiments have been carried out both in normal and in low-gravity conditions (attained onboard a ‘zero-g’ plane, during a parabilic flight campaign). The results have confirmed improved capability of the considered heat pipes with respect to traditional heat pipes filled with water.