Thermal Analysis and Improvement of Tablets

• Main Authors: Yuan-Jie Lin, 林淵傑
• Other Authors: Hwa-Chong Tien
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/45570929988620947728

碩士 === 國立臺灣海洋大學 === 機械與機電工程學系 === 103 === Today’s tablets possess high performance, stylish shape and compactness. As such, the operating temperature inside the tablets is increased. Moreover, thermal density increases due to the decrease in the thickness of the tablets. These factors greatly enhance the possibility of unexpected shut down. To solve the problem of waste heat accumulation, heat dissipation is enhanced via improvements in conduction due to limited space in the tablets, so that waste heat can be transmitted to ambient surroundings efficiently. This research conducts numerical simulations to obtain the flow and thermal fields in the tablets using a commercial code “FLOTHERM”, along with temperature measurements. The analyzed and the measured thermal fields are compared. The simulated results can be regarded acceptable if both results differ within 10%. Possible heat dissipation improvements are performed on high power components. Two major parts are included in study: PCB and the battery. Improvements can be cast into four categories: the PCB, the peripheral of the PCB, packaging of the chips, and conduction between the chips and EMI. It is hoped that these improvements render the high power components lower operating temperatures. Various improvements are selected and combined into a modified model. The average temperature for the original model in the tablet is 36.95℃ while the average temperature for the modified model is 30.72℃ corresponding to a drop of 6.23℃. This indicates that the proposed improvements are quite effective. It is observed that the waste heat can be transmitted evenly in different directions and to various locations in and out of the tablet. The proposed model performs satisfactorily.