A study of the thermal state of an element cooled by means of heat pipes

The cooling of a plane element by heat pipes with end-face rather than radial evaporation is investigated experimentally. Results are presented for four mesh-type heat pipes and a heat pipe with a metal-fiber structure consisting of 70-micron-diameter, 5-10-mm-long copper fibers. It is shown that heat pipes with end-face evaporation are efficient heat transfer devices. The evaporator temperature does not exceed 470 K up to heat loads of 250 x 10 to the 4th W/sq m for pipes with arterial inserts and 110 x 10 to the 4th W/sq m for pipes without the inserts. The performance of the metal-fiber heat pipe is practically equivalent to that of mesh-type heat pipes up to loads of 50 x 10 to the 4th W/sq m. Higher loads lead to a noticeable increase in the evaporator temperature of the metal-fiber heat pipe.