近年來，隨著輕、薄、短、小的需求與高性能微處理器的使用，散熱設計一直是筆記型電腦性能好壞的重要因素。本研究採用IBM T-40當作分析的模型，使用FLOTHERM 3.2對筆記型電腦系統內部進行散熱裝置之模擬分析，目標在達到理想的CPU溫度。首先，進行實驗以驗證FLOTHERM的準確性，實驗與模擬CPU溫度最大誤差為2.6%、熱阻最大誤差為5%，驗證FLOTHERM在熱分析上之準確性。
　　分析結果顯示，考慮風扇的位置及流道，離心式風扇(Blower fan)出口區風速能有效的作用在散熱片高溫表面，減少系統內部回流的發生。就鰭片厚度及其片數對散熱性能之影響而言，在基座面積為50mm2、鰭片片數24片、厚度0.6mm可得到一個最佳CPU溫度值。使用多根熱管能有效降低熱阻，但受限於冷凝端的散熱效率(小鰭片、低風速)，添加第三根熱管比使用二根熱管，熱阻約下降4%左右，差異很小。經整體模擬分析，RHE(Remote Heat Exchanger)散熱模組，總熱阻約為1.33oC/W左右；雙散熱片模組熱阻約1.29oC/W左右；雙風扇模組熱阻約為0.93oC/W左右。

　　In recent years, light, thin, short and small devices were developed and high performance microprocessors were used in notebook PCs. Thermal design is an important factor in the performance of notebook PCs. In this study, Flotherm 3.2 is used to simulate the cooling devices of notebook PCs, based on IBM T-40, to obtain the ideal CPU temperature. The accuracy of Flotherm is verified by experiment first. Comparing the results between experiments and simulations shows that the maximum deviation in CPU temperatures is 2.6%, and in thermal resistances is 5%.
　　The simulation results indicate, that a blower fan can direct the flow on the high temperature surface of heat sink effectively, and reduce the internal recirculating flow. An optimum CPU temperature can be obtained, For the heat sink with 50mm2 base area, 24 pins, 0.6mm fin thickness. The thermal resistance can be reduced by using heat pipes. However, constrained by the cooling efficiency of condenser section(small heat sink, low flow speed), thermal resistance can be reduced only about 4% with the addition of the third heat pipe. According to the overall system simulation, the thermal resistance of RHE thermal module is about 1.33oC/W, for the two heat sinks thermal module about 1.29 oC/W, and about 0.93oC/W for the two fans thermal module.

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