工業用個人電腦在自然對流下之散熱分析

Cooling Analysis of Industrial Personal Computer by Natural Convection

翟春郁(Chun-Yu Chai)

指導教授 ： 李基禎 ； 郭鴻森

大同大學/工程學院/機械工程學系所/碩士(2009年)

摘要

近年來，隨著輕、薄、短、小的需求與高性能微處理器的使用，散熱設計一直是工業用個人電腦性能好壞的重要因素。傳統的電腦散熱方式主要以氣冷為主，隨著散熱量需求的增加，必須不斷地提高風扇轉速，才能確保散熱效果，但伴隨而來的是風量及風壓增高所產生越來越大的噪音。在此種情況下，熱導管與水冷式的散熱模組有漸取代傳統散熱方式，成為市場的主流的趨勢。
本研究主要是針對某公司所提供的工業用個人電腦之模型進行自然對流下的散熱分析，內部透過導熱管快速地將CPU及北橋晶片產生的熱傳遞至散熱鰭片將熱散去，使系統得以快速降溫。此種方式之散熱系統稱為RHE（Remote Heat Exchanger）散熱模組，可解決噪音問題，提升散熱效果。
採用套裝軟體PHOENICS來模擬分析具熱源之工業用個人電腦的散熱情形。考慮所欲改變的參數為導熱管數量、散熱鰭片、重力方向、開孔率等。由以上參數的改變，針對工業用個人電腦幾何構造之三維流場作數值模擬，分析後得到其內部速度流場及溫度流場變化的結果，並探討其散熱在自然對流模式下最佳的配置與CPU最佳溫度值。
經整體模擬分析，改變其重力方向後，溫差相差約20~30℃，透過RHE與適當的開孔率，可使CPU得到最低的溫度值85.6℃。

關鍵字

導熱管 ； 散熱鰭片 ； 自然對流 ； 散熱模組 ； 工業用個人電腦

並列摘要

In recent years, light, thin, short and small devices were developed and high performance microprocessors were used in industrial personal computer. Thermal design is an important factor in the performance of industrial personal computer. The traditional way of cooling the computer is based mainly on air cooling. With the increased demand for heat dissipation, it must continue to improve the fan speed to ensure the cooling effect. But it will increase air volume and air pressure and then increase the noise. In this situation, heat pipes with water-cooled cooling modules have become a mainstream trend in the market to replace the traditional cooling methods.
In this study, an industrial personal computer provided by a company is used for the thermal analysis of natural convection. Through suitable arrangement of heat pipes to obtain a rapid cooling system, the heat generated from CPU and north bridge chip can then be dissipated quickly. Such method is called as RHE（Remote Heat Exchanger）method which can solve the noise problem and also enhance the thermal effect.
The software of PHOENICS was used to simulate the heat transfer characteristic in the industrial personal computer. In the present study, the desired parameters of analysis are the number of heat pipe, cooling fin, gravity direction, and opening rate.
According to the analysis of 3-D numerical simulation by natural convection on the industrial personal computer, here can get distributions of inner speed and temperature and also find optimal configuration of cooling analysis in the industrial personal computer. Afterward, the lower CPU temperature can be obtained.
Based on the overall simulation, temperature will decrease about 20℃ to 30℃ by changing the direction of gravity. Through suitable arrangement of RHE and open rate, the lower CPU temperature is able to get 85.6℃.

並列關鍵字

Natural convection ； Heat sink ； Remote Heat Exchanger ； Industrial personal computer ； Heat pipe

參考文獻

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