台灣的古蹟在政府相關單位推動修復且再利用的同時，往往過度保護且過於依賴空調設備，而忽略了原有節能設計，在目前極力推廣自然通風綠建築的理念下，實需多學習前人在舊式建築上如何與大自然共生共存之道。
本研究利用CFD軟體對日式木構造建築，進行內外流場之模擬分析，在不影響室內作業的前提下，探討在原有的通風設計與不同氣候條件時，室內熱舒適性環境之變化，評估日式木構造建築自然通風的可行性。
從CFD分析結果可以得知，若能充分利用原有的氣窗設計，夏季室內的平均風速能上升22%，平均溫度下降1.6K；春季室內的平均風速更是上升31%，平均溫度能下降1.4K。可見自然通風除了可提升室內環境之舒適性，也能減輕空調能源負荷。另外本研究也針對室外風速與室外溫度對於自然通風效益之影響進行討論，並利用CFD建立了3到11月份自然通風後之結果，以供參考。

The government agencies have repaired some monuments in Taiwan and activate adaptive reuse of the space. However, they often overprotect the monument and overuse air-conditioning, which ignore the original energy saving design. Under the trend of natural ventilation for green buildings, we need to know more about how the ancients coexisted with the nature in old buildings.
This study used CFD software to simulate indoor and outdoor air flow for Japanese Wooden Building. Without affecting current indoor operations, I studied the thermal comfort of indoor environment by the original ventilation design under different climate conditions. The feasibility of applying natural ventilation in Japanese Wooden Building was also evaluated.
The numerical simulation results show that if we use the original transom design effectively, the average indoor velocity will be increased by 22%, and the average indoor temperature will be reduced by 1.6K in summer; also, the average indoor velocity will be increased by 31%, and the average indoor temperature will be reduced by 1.4K in spring. This effect of natural ventilation can not only enhance the thermal comfort of the indoor environment, but also reduce the energy load of air conditioning, which reach the concept of green buildings. In addition, this study discussed the effectiveness of natural ventilation by outdoor velocity and temperature, and then provided the results using natural ventilation by CFD from March to November.

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