Visualized of Improving the Evaporative Heat Transfer of a Thin Vapor Chamber with Binary Mixture Working Fluids

• Main Authors: Zih-Ci Su, 蘇子淇
• Other Authors: 張建成
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/7xkz8c

碩士 === 國立臺灣大學 === 應用力學研究所 === 107 === Today’s electronic products continue to evolve toward thinness and versatility. The development makes the product’s internal CPU generate more high heat. According to research, 55% of the damage of electronic products comes from the internal high temperature, the following are man-made and wet damage. It seen that heat dissipation plays an indispensable role in the development of technology. However, in pursuit of product thinning,the fluid quality must be decreased. The fluid quality is too less to load higher wattages. Therefore, the purpose of this experiment is using the Marangoni effect of the binary mixed fluids to enhance the flow from the condenser zone to the evaporator zone, delaying the occurrence of dry-out and increasing the critical heat transfer. In order to observe the internal dry-out phenomenon of the vapor chamber, we set up a visualized device, which can clearly observe the internal phase change and dry-out through the PC plastic upper cover. In terms of experimental fluids, we use pure water, 1-Butanol, 1-Pentanol and 1-Hexanol. In terms of concentration, the maximum solubility of each alcohol is selected. The concentration of 1-Butanol is ranging from 2~ The concentration of 1-Pentanol is ranging from 1~ The concentration of 1-Hexanol is only used in 0.6%. Changing the aboved fluids and concentration, and using the visualized heat device to measure the thermal resistance and take the internal photos. The results show that the critical wattage of pure water is 7W and the lowest thermal resistance is 3.146(°C/ For 1-Butanol, the 6% butanol aqueous solution has the best effect, the critical wattage is 11W and the lowest thermal resistance is 2.441(°C/ For 1-Pentanol, the 3% pentanol aqueous solution has the best effect, the critical wattage is 9W and the lowest thermal resistance is 2.596(°C/ For 1-Hexanol, the critical wattage is 7W and the lowest thermal resistance is 2.49(° C/W). From the aboved results,compared with pure water, the binary mixed working fluid has a significant increase in the critical wattage and has lower thermal resistance. Among binary mixed fluids, the 6% butanol aqueous solution has the best effect, the critical wattage is increased by 57% than pure water. Therefore, the 6% butanol aqueous solution is most effective on thin vapor chamber.