筆記型電腦功能日益強大，加上空間及電子零件的縮小，其散熱問題非一般桌上型電腦的散熱模組可以解決，需要設計更大效率的散熱模組。因此，為了要解決功能日益強大筆記型電腦的散熱問題及所具有的高阻抗系統特性，本文除了考量散熱風扇的尺寸設計，對離心風扇作幾何參數上的研究，透過數值模擬將風扇流場可視化，進行物理現象分析，從中找出性能最佳的風扇；另外再配合風扇出口面的模擬流場設計流線型散熱鰭片，藉由兩者系統化設計考量，期望將散熱模組之最佳性能表現出來，改變市面上散熱座與風扇之間分開製作的現況。在風扇部分的結果，透過幾何參數的改變，其中包含了進風口直徑、蝸型外殼、葉輪型式及遮蔽效應等，可發現使用理論計算之入口角搭配翼型之葉片，在相同外殼上，流量方面較原始設計提昇了25.9％，靜壓方面則可增加12.2％。在散熱座方面，除了依據風扇出口流場來設計流線型鰭片散熱座外，再設計一款等散熱面積的直板型鰭片散熱座以作為對照組。經實驗比較後發現其散熱效果超出預期，流線型鰭片散熱座在設計方式上需要考量更多因素，例如改變散熱座形狀。透過風扇與鰭片系統化設計，即可提高筆記型電腦散熱模組的散熱效率與降低噪音。

The space within a notebook computer is running out when extra components are included in the system; therefore, a high-efficient thermal mould is in great demand and becoming the topic of this research. A streamlined heat sink is designed to incorporate with a centrifugal fan for meeting the thermal challenge of a Pentium M770 processor with 27W power consumption. At first, a comprehensive parametric study on a centrifugal fan is executed to generate a cooling fan with better performance. Next, the numerical simulation on this blower (60×60×15mm3) is performed by using STAD-CD code. Later, the detailed flow field at the fan outlet is visualized numerically and utilized to design the streamlined fin geometry, which matches the flow pattern appropriately and minimize the resistance to the passing airflow. Thereafter, a prototype cooling fan and the heat sink are fabricated via a CNC machine and used to carry out the experimental verification. The outcome of parametric study on fan geometry results in 25.9% and 12.2% increases on airflow and static pressure, respectively. However, the improvement on thermal capacity of the streamlined heat sink is not as expected based on the experimental work. Obviously, there are more alternatives needed for designing a heat sink, such as selecting a non-rectangular base for heat sink. In summary, the measurements agree with numerical outcomes in this study. Moreover, a systematic design scheme, which generates the cooling fan and fin simultaneously, is established successfully and may provide a possibility to reduce the noise output and enhance the thermal performance of heat sink assembly for notebook computers.

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