筆記型電腦的散熱技術一直是需要不斷的開發與研究的。隨著電腦內部散熱問題的日益嚴重，除了尋求更創新的散熱方案之外，應確實改善原有的散熱設計缺失，進而有效地將廢熱移除於功率逐漸增強的電子電路之中。因此如何正確與有效的應用數值分析軟體，使我們能夠更進一步了解電腦系統內部的散熱狀態與行為模式，從而分析與改善電腦系統內部散熱機制使其達到理想的操作環境溫度與CPU核心溫度，為本論文主要的研究方向與目標。
本論文的研究主要偏向於改善筆記型電腦系統之散熱設計，並整理出一套如何有效進行筆記型電腦散熱設計的分析程序與方法，並將個人的研究心得與建議做一份完整的報告。首先，我們使用FLOTHERM 2.2模擬分析軟體，對現有的筆記型電腦進行初步模擬分析。並藉由其模擬計算的結果，從中細部分析與探討系統中熱量與氣流的傳遞行為模式。其次，我們針對其熱設計上的缺失提出具體的改善對策(如：消除熱區、優化風扇效能及散熱片改良設計等)。我們將依照所提出具體的改善方案來進行系統內部的散熱設計，同時將CPU單位體積的散熱功率提升為原來的三倍，並將筆記型電腦系統內部的最高溫度值控制在比先前初步模擬分析所得溫度之下，來證明新的散熱設計組合有更優越的散熱能力。

經由模擬分析之結果，我們可以歸納以下幾個結論：(1)我們考慮風扇的出口方向與其裝設的位置，將其擺放至散熱片的高溫分佈區域，並配合風扇出口的空氣流速加以改善原有散熱片的設計。經由比較性模擬(使用與筆記型電腦初步模擬相同發熱功率的CPU元件)，其系統中發生的最高溫度比起在初步分析中的溫度低了將近27°C。(2)為了有效避免在散熱片表面上經由對流所散出的廢熱會經由向上之對流擴散而停滯在電腦系統內部之中。因此，我們考慮導管型散熱片的設計，並於導管內部進行強制對流散熱，經由模擬分析結果其可為系統帶來額外1°C至3.5°C的溫降空間(視導管內部散熱片數量而定)。(3)由於在導管內部設置散熱片會嚴重影響風扇出口的流速，因此我們將散熱片移至導管外部以自然對流的方式進行散熱，經由模擬分析結果其最佳自然對流散熱條件可為系統帶來額外6°C的溫降空間。(4)由於銅材的熱傳導系數約為杜拉鋁材的2.5倍之多，因此我們考量其優越的熱傳導性能並顧及其加工製造上的不便性，試著以配合銅材的設計方式，將散熱導管的CPU承熱鋁片改用為銅片，經由模擬分析結果其可為系統帶來額外17°C的溫降空間。(5)最後考量其風扇只具有單一之側出風口，可能會造成風扇系統內部過大之壓力產生。因此在筆記型電腦有限的空間內部，我們考慮雙導管型散熱片的設計，經由模擬分析結果其可為系統帶來額外12.4°C的溫降空間。

Notebook heat dissipation technique(s) has always been a subject with continuous research and development needs. The necessity to improve existing methods of heat dissipation and develop new dissipation techniques, is particularly important in the face of improved electronic circuitry efficiencies. In this regard, the objective of the present thesis is to investigate and discuss the appropriate use of Applied Numeric Analysis software for the purposes of understanding how and under what conditions heat dissipation occurs, in order to achieve improvements in current heat dissipation techniques, and to attain ideal CPU temperature and internal systems heat control.
We began our study by first using the Flotherm 2.2 simulation software to provide a basic internal notebook systems thermal analysis. Results of this initial simulation was used to analyze current and systems heat flows, which served as the basis for our recommendations to improve existing heat dissipation techniques such as the elimination of heat pools, and the enhancement of heat sink and ventilation fan designs. The recommendations were then used for the design of an improved heat dissipation method that increases per unit volume CPU heat dissipation efficiency by three times the original, while maintaining the same internal systems maximum temperature.

Making comparisons between the initial laptop internal systems analysis and analysis using recommended heat dissipation techniques, we have arrived at the following conclusions and recommendations:

1.Considerations were given to the placement and direction

of the ventilation fans: Recommendations were given to

placing ventilation fans around high temperature areas in

the heat sink, and the redesign of existing heat sinks

with considerations given to fan air flow. Simulation

comparisons revealed that identical CPU parts had a peak

temperature decrease of approximately 27°C.

2.Consideration was given to the aggregation of heat pools

that result from convection currents above heat sinks:

Recommendations were given to the design of duct style

heat sinks, and the use of forced convection within the

ducts. Simulation comparisons revealed that, depending on

the number of ducts used, there was a 1.0°C to 3.5 °C

improvement in internal temperature reduction.

3.Consideration was given to the reduced ventilation air

flow speed as a result of the duct placement:

Recommendations were given to placing the heat sinks

external to the ducts to allow for heat dissipation using

natural convection methods. Simulation comparisons

revealed that there was a 6°C improvement in internal

temperature reduction.

4.Considerations were given to the use of copper versus

duraluminum due to the better thermal conductivity of

copper (2.5x of duraluminum). Consideration was also

given to additional assembly requirements of copper.

Recommendation was given to the use of copper CPU chips

within the ducts. Simulation analysis revealed that there

was a 17°C improvement in internal temperature reduction.

5.Consideration was given to the singular air current flow

that may result in heavy pressures on the ventilation

system. Recommendation was given to the use of dual duct

heat sinks. Simulation comparisons revealed that there

was a 12.4°C improvement in internal temperature

reduction.

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