Experimental investigation into the performance of heat pipe with micro grooves fabricated by Extrusion-ploughing process

Heat pipe with groove-shaped capillary structure always shows smaller heat transfer limit. It is because that traditional fabrication technique leads to the difficulty in minimizing the geometric dimension of grooves. As a result, novel fabrication technique is of great importance. In this paper, we will discuss some heat transfer characteristics of heat pipe fabricated by novel Extrusion-ploughing process. Owing to the extrusion from tools in the fabrication course, two kinds of grooves, namely leading grooves and secondary grooves, are formed in this kind of heat pipe. This feature will polish the groove geometric structure. Furthermore, considering the fact of parallel combination of these two kinds of grooves, excellent heat transfer performance of novel heat pipe fabricated by novel Extrusion-ploughing process can be expected. The experiments of testing temperature changes versus time at evaporator sector and condenser sector at different work temperature are conducted. The temperature distribution along axial direction of this kind of novel heat pipe at its steady stage is also tested. The experimental results prove that the heat pipe fabricated by Extrusion-ploughing process exhibits ideal isothermal performance and excellent heat respond speed. When compared with normal axially grooved heat pipe, this novel kind of heat pipe also shows larger final heat transfer limit. (C) 2010 Elsevier Ltd. All rights reserved.