交換電源供應器之散熱分析

Analysis of Heat Dissipation in Switching Power Supply

鐘士智(Shih-chih Chung)

指導教授 ： 郭鴻森

大同大學/工程學院/機械工程學系所/碩士(2004年)

摘要

本文主要討論明緯（MEANWELL）公司500W-5V交換電源供應器SPS(Switching Power Supply)模擬分析其散熱性能之研究。研究主要內容針對兩個重點，一是原幾何尺寸架構下的散熱分析，二是修改內置鋁擠型散熱片的外型與強制對流方向改變來討論，本文分別以FLOTHERM這套CFD套裝軟體來做數值模擬方面的分析，針對此兩種型式之各項參數進行探討。
鋁擠型散熱片的外型設計會影響SPS的流場分佈，經由流場分佈的結果可發現較佳的散熱模型，因此藉由修改相關尺寸與強制對流方向，並考慮散熱片與風扇的距離，讓進風處的空氣能有效經過扁長型鰭片通道產生良好的空氣流動，並能夠帶走SPS運作時所產生的熱量，並提高SPS整體的流場與散熱效能。結果顯示，風扇採用吹入方式的安裝時，需要與鋁擠型散熱片有較長的安裝距離，才有較佳的流道狀態。但強制對流吹入處的阻礙使流道改善遠不及改以強制對流吸出來的好。因此，在未來SPS的設計上，可供散熱片外型設計與風扇相對位置關係及內部電子零件佈置改進參考。

關鍵字

散熱 ； 交換電源供應器

並列摘要

This thesis is a research simulating and analyzing the heat dissipation performance of the Meanwell's 500W-5V switching power supply (SPS). In this research, there are two main points for discussion. The first is the heat analysis under a structure of original geometry, and the second is both an alteration in the profile of built-in aluminum extrusion-type heat fins and a change in forced-convection direction. With the CFD software Flotherm, this research conducted numerical simulation analysis for parameters of the two types separately.
The profile design of aluminum extrusion-type heat fins will influence SPS flow field distributions. From the results of flow field distribution, a better heat dissipation model can be found. Therefore, by altering related sizes and forced-convection direction and taking into account the distance between the heat fins and the fan, the air at the inlet is enabled to effectively pass through the flat fin channel to produce excellent airflow, carry away the heat produced during SPS operations, and enhance the efficiency of the flow field and heat dissipation of the SPS as a whole. The result shows that when the fan is installed by means of blow-in, a longer installation distance is needed to the aluminum extrusion-type heat fins in order to achieve a better channel status. However, the obstruction at the forced-convection blowing port makes channel improvement far inferior to forced-convection suction. As a result, for future SPS design, this research can provide improvement and reference for relation between heat fin profile design and a fan's relative positions, as well as deployment of electronic parts.

並列關鍵字

analysis ； switching-power

參考文獻

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