筆記型電腦之散熱系統 設計與分析研究

Analysis and Design of A Cooling System on Notebook Personal Computers

鄭建都(Chien-Th Cheng)

指導教授 ： 王世明

中原大學/工學院/機械工程研究所/碩士(2004年)

https://doi.org/10.6840/cycu200400577

摘要

本文主要探討筆記型電腦內部流場暨散熱系統分析。藉由FLOTHERM軟體來模擬電腦內部各發熱元件，並求解因系統開孔而產生的速度場、壓力場與溫度分佈。為了確定數值模擬的正確性，同時並實驗觀察加以驗證。利用溫度擷取系統來讀取各主要發熱元件溫度，利用滑石粉來觀察系統流場趨勢，結果顯示數值模擬結果與實驗接近。
在本研究中針對散熱模組的鰭片長度的部分，當鰭片長度為15時，CPU溫度為75.9℃，VGA為98.2℃，而當鰭片長度為20時，CPU溫度為75.8℃，VGA為98.9℃，可見系統與CPU溫度不是絕對的。若底殼與主機板之間距離固定，在兩者之間沒有其他介質其底殼溫度為最佳，若需加入其他材料增加系統穩定度則以其與底殼距離為零，底殼溫度最好。在開孔問題上，在風扇正下方開孔對於CPU可以得到最佳狀況，但對於其他元件並不是最有利，對於系統最佳則是使流場流經各元件以達到系統降溫。

關鍵字

筆記型電腦 ； 散熱 ； 冷卻系統

並列摘要

The present study focused on the analysis of A cooling system for Personal Notebook Computers. Flotherm commercial software was used to simulate heating components inside notebook and to evaluate the velocity field, pressure field, and temperature profile. To ensure the accuracy of the numerical results, combining simulation with the experimental measurements were conducted to verify at the same time. Utilizing temperature fetch system to record and read temperature of heating components. To observe the flow trend of system, put talc powders were uesd, and the result reveals that numerical and experimental consequences were in coincidence.
The lengths of fins of thermal module have certain influence on CPU temperature. According to the analysis, it is noted that the system and CPU temperatures are not correlated. When the distance between bottom case and motherboard is fixed, and there are no other materials between them, it will have better cooling effect at bottom skin. If it is required to have other materials in between to enhance system stability, the material should stay as close as possible to bottom case. For openings, it will have the best status for CPU with cooling holes under cooling fan directly. For the whole computer system, the optimum design is to yield airflow through heating components to get larger temperature drops.

並列關鍵字

Thermal ； cooling system ； notebook

參考文獻

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