空氣簾流場模擬與節能效益研究

The study of energy conservation and flow field simulation for air curtain

李國仲(Kuo-Chung Lee)

指導教授 ： 郭鴻森 ； 李基禎

大同大學/工程學院/機械工程學系所/碩士(2006年)

摘要

自從計算機發展以來，由於計算速度不斷增快，計算成本可不斷降低，利用流體力學CFD軟體計算達成室內環境節能的例子越來越多，尤其在台灣能源百分之九十八以上仰賴進口。而近年來國內能源用量不斷增加，台電於夏季尖峰用電量更是屢創新高，節約能源及提昇能源效率為當務之急，如何應用CFD軟體來減少不必要的能源消耗為節能的重要課題。

本文利用商業CFD軟體PHOENICES分析模擬便利商店於店內門口處，在未裝空氣簾前與安裝空氣簾後室內氣流場與溫度流場的分佈，藉由氣流場與溫度流場模擬得出室內風速與溫度，進而得到便利商店內整體流量分佈與熱傳方向。再由現場量測所得到室內風速值及溫度值，藉由數值分析模擬，得知空氣簾風速強弱會影響室內空調系統耗能。當空氣簾風速太強時，所產生的簾幕氣流會與室內外氣流互相衝擊擾動，造成室內冷熱氣流混雜，影響購物環境舒適度；當空氣簾氣流風速太弱時，無法有效隔絕室外溫度侵襲室內所造成的溫度自然對流現象，節省室內空調耗能。

設置空氣簾，可維持室內冷(暖)氣效果，同時達到舒適的節能，若能與自動門的搭配，更可發揮空調系統效率。就實驗中模擬便利商店10.8m*6.8m*2.8m空間內，為開放式場所，在安裝空氣簾後，設定五種不同的風速，分別驗證節能效益。實驗得知當不安裝空氣簾時，冷氣流量損失為5.87 kW；在安裝空氣簾後風速設定為2m/s時，損失為3.47kW，節能效益達60% ~ 70%，因此得知在開放式場合的商店內加裝適當空氣簾後是可減少空調系統長時間的運轉，並循環調節溫度達到節能效果。

關鍵字

空氣簾 ； 節能 ； 空調系統 ； 自動門 ； 便利商店 ； 氣流場 ； 溫度場

並列摘要

Since the invention of calculators, the speed of calculation continued to increase and calculation costs continued to decrease. Through fluid mechanics CFD software calculations, more successful examples of indoor environment energy conservation have been reported. In Taiwan, more than 98% of energy supplies rely on imports. As domestic power use continues to increase, the shortage of power supply from Taiwan Power Company repeatedly exists in summer. Therefore tasks of saving energy and raising efficiency become top priority. How to use CFD software applications for reducing unnecessary energy consumption is an important issue for conservation energy.

This text has adopted commercial CFD software PHOENICES analysis in simulating flow field and temperature field distribution inside the convenience store for entrance with air curtain. Through this simulation the indoor air velocity and temperature are attained, and get the overall flow distribution and heat conduction direction inside the convenience store. Through onsite measuring to indoor air velocity value and temperature value for using numerical analysis. It shows that air curtain wind velocity intensity indeed affects indoor air-conditioning system energy consumption. When air curtain wind velocity is too strong, outside air and inside air will be the air curtain current, causing mixed cold and hot air indoor and affecting shopping comfort. When air curtain velocity is too weak, it is impossible to isolate the outside air from causing natural convection heat transfer, and to reduce indoor air-conditioning energy consumption.

The installation of air curtain can maintain the effect on the heat (Coldness) of the air. At same time it improves the comfortableness and saving of energy. If an automatic door is available, better air-conditioning system efficiency is facilitated. Inside experimentally simulated the convenient store open space measuring of 10.8m*6.8m*2.8m, after installing air curtain, There are use 5 levels are set to monitor energy conservation result. The experiment shows that when the air curtain is not installed, cold air loss is 5.87 kW, after the air curtain is installed with wind velocity set at 2m/s, the cold air loss is 3.47kW. To benefit it s energy conservation is 60% ~ 70%. Therefore, it shows that installing appropriate air curtain inside an open-type of convenience store space helps reducing long-standing operation of the air-conditioning system, recycles and regulates the temperature to achieve energy conservation results.

並列關鍵字

AIR CURTAUN ； ENERGY CONSERVATION ； AIR-CONDITIONING SYSTEM ； Convenience store ； Temperature field ； Flow field

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