地道風系統節能效益分析

Analysis of Energy Conservation of Underground Labyrinth System

吳泓連(Hong-Lian Wu)

指導教授 ： 李文興

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)

摘要

本文主要在探討廠房設置地道風系統與未設置地道風系統之間的節能效益，並找出適合本氣候區的地道風系統方案。而模擬模型則是位於大陸常州地區廠房之實際案例。
地道風系統利用蓄存在土壤中的地熱能冷卻或加熱外氣，並由機械送風或誘導式通風將室外新風送入室內，改善室內環境狀況，外氣經地道風系統後，空氣與地道進行熱交換，傳至地底下之熱傳量即為減少的空調負荷，達到節能效果。
研究方法運用CFD (Computational Fluid Dynamics)數值解析方式，採用計算流體力學模擬軟體ANSYS Airpak 3.0。模型的模擬採取現有地道風系統之模式，並提出增進之策略，進而由模擬結果計算評估節能效益。
大陸常州廠房因設置地道風系統後，在各個外氣條件下，現有隔板型式在夏季外氣27~32℃時約可降低空氣溫度0.4~1.6℃；在冬季外氣1~12℃時約可升高空氣溫度1.4~4.0℃。因此應用地道風系統，由節省空調負荷之耗電量來看，在夏季與冬季總節省空調用電約12,769度電。採行增進策略，增加隔板比現有隔板形式夏季增加84.7%節能效益及增加小天花板冬季增加5.4%節能效益，總預估年節省夏季與冬季空調用電量可增至16,573度電。

關鍵字

地道風系統 ； CFD數值模擬 ； 計算流體力學

並列摘要

The main purpose of this thesis is to discuss the energy performance of a factory with and without Underground Labyrinth System and to figure out which type of Underground Labyrinth System is suitable for the designated climate. The factory located at Chang Zhou, Mainland China is used as the practical example of this simulation model.
To modify indoor’s temperature, Underground Labyrinth System employs the geothermal energy in the soil to cool and heat the external air and uses mechanical ventilation allowing air flow from outdoor to indoor. After external air flow into Underground Labyrinth System, the air transfers heat to or receives heat from the tunnel. This kind of heat transfer reduces the work of air conditioner and achieves energy efficiency.
The research adopts Computational Fluid Dynamics simulation software of ANSYS Airpak 3.0 and uses the numerical methods and algorithms of CFD to analyze the data. Based on the current existing Underground Labyrinth System and with furthered proposed improved methods, we then evaluate the result of energy performance of the simulation model.
With Underground Labyrinth System, the internal temperature of the factory at Chang Zhou has changed. In summer, when the external temperature is 27-32℃, the internal temperature will decrease around 0.4-1.6℃. In winter, on the other hand, when the external temperature is 1-12℃, the internal temperature will increase around 1.4-4℃. Therefore, with underground labyrinth system, the air conditioner has total saved 12,769kWh in a year. Furthermore, we can save more energy with improved methods. With more partition boards installed in the factory, we can save 84.7% of energy in summer and with more ceiling installed, we can save 5.4% of energy in winter. Thus, the total estimated energy saved on air conditioner is increased to 16,573kWh in a year.

並列關鍵字

Underground Labyrinth System ； Computational Fluid Dynamics（CFD）

參考文獻

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[1] 鄭愛平，地道風應用分析與計算，西北建築工程學院，西安，2000年。