Sharif Digital Repository

technologies for cooling of electronic devices, have high efficiency due to the heat transfer in two-phase state. In this project, experimental effects of asymmetric triangle groove has been studied on the boiling fluid and effect of the motion on the boiling and heat pipe. Therefore, the experiment has been done by 3 heat pipes and each with 3 plates. The plates consist of a smooth plate, a plate with triangle groove and a plate with rectangle groove. Each heat pipe was filled by methanol in volumetric percentage from 10 to 60. The results show that 20 percent methanol is the optimum for all kind of heat pipe, which has been used. In addition, it is shown that heat pipe with triangle groove... 

The use of nano-fluid, which is a stable solid liquid mixture, has been proposed as a new strategy for heat transfer operations. Much research has been done on heat transfer of nano-fluids until now, whereas the study of phenomena associated with phase change, such as boiling where there is heat transfer in larger scales is very necessary. The boiling process based on its potential for transferring high amounts of heat at low temperatures is a very effective and common mechanism, and it occurs in many engineering systems, including boilers at plants, evaporators in refrigeration systems and nuclear reactors. Also, a considerable amount of research was done recently in the field of... 

Improving the discharge process of phase-change materials (PCMs) is of great importance. In this study, the process of acetone drop impact on molten paraffin, as a direct-contact solidification method, is experimentally investigated. Four Weber numbers (corresponding to heights of 10, 20, 30, and 40 cm) for the acetone drop and six surface temperatures (66, 68, 70, 75, 80, and 90 °C) for the molten paraffin are considered. As the acetone drop impacts the molten paraffin, the drop absorbs heat from the melting paraffin and boils, solidifying a portion of the molten paraffin. Two important parameters that govern the acetone drop dynamics and the solidification of the molten paraffin are the...