週期性擺動之送風葉片對室內空間氣流分佈的影響

The Effect of an Air-Supply Guide Vane with Periodic Swing on the Indoor Air Distribution

陳文豪(Wen-Hao Chen)

指導教授 ： 施陽正

國立臺北科技大學/機電學院/能源與冷凍空調工程系碩士班/碩士(2011年)

https://doi.org/10.6841/NTUT.2011.00202

摘要

空調設備的主要目的為提供空間內各區域舒適以及恰當的室內空氣品質，其中最重要的步驟就是空間內空氣的溫度、流動度維持在可接受的情況下將空間內的熱給與消除。利用一個噴流將吹入空間中以誘導空間內的空氣一起流動，並且加入週期性擺動葉片增加空間內流體的流動性，藉著引入的冷空氣將人員區內的熱量給予帶走。
本研究中以商用套裝軟體FLUENT 6.3分析不同振幅與頻率組合下葉片擺動對空間內流場分佈情況，由模擬之結果可知葉片擺動振幅為影響空間內氣流分佈的主要因子，當葉片擺動角度過大會使噴流產生分流現象，此時空間內渦流強度變大，可增加噴流與空間內流體的混合性。最後由流線圖以及溫度圖觀察可知噴流會沿著底部並朝著出口流出，大部份的熱藉由此流動方式給排出，而室內的流體及部分噴流會沿著右壁面及天花板回流到噴流，此種現象增加室內空間的流動性與熱傳性提供絕佳的混和效果，並且可保證整個空間的溫度具有一定程度的均勻性。

關鍵字

紐賽數 ； 頻率 ； 振幅 ； 計算流體力學 ； 動態網格 ； 康達效應

並列摘要

The main purpose of air-conditioning is to provide comfort and appropriate indoor air quality. One of the main tasks of air-conditioning is to control the air temperature and flowing pattern within an acceptable level in order to remove heat from the space. Using a jet to induce air into the space with periodically-swinging fin, the mobility of the air can be increased and hence the heat in the occupied zones can be removed by the jet of cold air. This study uses FLUENT 6.3, which is commercial flow analysis software, to analyze the main factors affecting the air flow distribution under the effect of swinging fin. When the sweeping angles of the fin are large, the air flow splits, causing the eddy current to grow with greater turbulence intensity and hence enhance better turbulent mixing in the space. Finally through the flow pattern analysis and temperature distribution analysis, it is observed that the air stream will flow along the bottom face of the space towards the exit. Most heat is removed through advection carried by this flow. Meanwhile, the room air and part of the jet flow will flow along the ceiling and right wall and then re-circulated back to the jet. This phenomenon increases the mobility as well as heat transfer of the room air and provides excellent mixing effect of the air streams. Hence, a certain level of uniformity of the room air temperature can be assured.

並列關鍵字

Nusselt number ； Frequency ； Amplitude ； Computational Fluid Dynamics ； Dynamic Mesh ； Coanda Effect

參考文獻

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