雨屏牆構法系統是由外部雨屏、內部氣屏與中空層所構成的外牆構造，藉外氣導入中空層來達成雨屏內外的等壓行為。等壓性能的優劣會影響中空層的排水性能與雨屏之風載。歐美國家對雨屏研究發展至今約有60年，初始乃由防水觀念而起，再衍變為以開放式接縫達成等壓來排水，提出利用等壓可減輕雨屏風載的相關研究，但各參數在減輕風載的標準尚未一致。相對地，與國外比較，台灣相關的應用研究不多，惟以台灣季風與多颱風的氣候環境下，外牆風載的設計是相當重要的一環；雨屏牆除了可以減輕雨屏風載外，其所節省之外牆結構與材料費用也相當可觀，乃一值得應用的外牆構造方法。

本研究經由文獻，彙整影響等壓雨屏牆風載的因子，以點支撐雨屏牆構法為研究對象，透過風洞實驗、計算流體動力學的數值模擬測試以及水桌實驗的流場檢視，並與文獻比對；研究結果歸納如下三項，以供未來訂定雨屏牆風載設計之參考：
1、以風洞實驗分析雨屏牆之風載
以長寬高為1：1：1雨屏牆試體，正面迎風時，在0.6%的透風開孔率下，就開放式接縫、圓形透風孔及條狀透風孔三種透風形狀之雨屏而言，以條狀透風孔所受風載最小；在透風開孔率0.6%～3.3%的範圍，透風開孔率愈大，等壓性能愈好，故所受風載愈小。中空層容積在0.04 到0.16 m3的範圍，其對雨屏風壓差影響不明顯。非均勻流(α＝0.15)與均勻流況之比較，雨屏等壓性能以均勻流優於非均勻流，均勻流況可達等壓性能80%，非均勻流況約達73%等壓性能。當面對不同風向時，風向角在60°～90°之間，等壓性能可能較差，因此雨屏所受風載有變大趨勢。
2、數值模擬雨屏牆風載之適用性
以CFD商用軟體Fluent標準k-ε紊流模式模擬，當正面迎風時，開放式接縫雨屏透風開孔率為0.6%～3.3%，等壓性能比風洞實驗值較高，建議減少約4%之修正值，可接近於風洞實驗結果。但風向角改變後，結果與風洞實驗有些微差異，對於由數值模擬雨屏牆風載之關係，在風向角45°～135°之間，待進一步檢討與模擬。
3、水桌實驗檢視雨屏牆流場結構
由水桌實驗可視化流場分析雨屏與氣屏正負壓的行為，與風洞實驗行為是相似的，在風向角60°～75°，雨屏出現正負壓的臨界角，同風洞實驗風向角75°時，雨屏內外可能出現較大的壓差，所以可由水桌實驗來輔助瞭解雨屏流場行為。

Pressure equalized rainscreen (PER) wall is the combination of an external rain screen, an internal air barrier and an air cavity in between. The pressure equalization is achieved by introducing the outside air into the air cavity. The performance of pressure equalization rainscreen affects both the watertightness and the wind loading of the rain screen. Rain screen walls have been developing for the last 60 years in America and Europe, initiating from waterproof to recent wind load reduction. However, no standard or guideline is presented to describe how various parameters contributing to the wind load reduction on the rain screen. In contrast, there are relatively not many application studies in Taiwan. However, PER wall is very important in Taiwan, due to frequent reasons and many typhoons. Especially PER walls can increase safety of exterior walls by reducing wind loading through pressure equalization. Thus, this research aims to investigate how various parameters affect the wind loading on the PER walls by both experiments and CFD simulations, employing point support system. The key results are as follows：
1. Wind loads on PER walls via wind tunnel test
The results of wind tunnel test indicate that the pressure equalization performance on rain screen wall with strip is better than those with other geometries. As the vent hole area ratio increases for the range from 0.6% to 3.3%, the pressure equalization performance increases, an indication of a smaller pressure difference across the rain screen. For the range of cavity volumes from 0.04 to 0.16m3, the cavity volume has no significant effect on the pressure equalization performance. The percentage of pressure equalization can be obtained around 80% at least under uniform flow conditions and 73% at least under non-uniform flow conditions (profile exponent α=0.15). For the cubic model, the wind directions from 60° to 90° give a lower pressure equalization performance.
2. The suitability of evaluating wind loads on PER walls by using numerical method
At the wind direction of 0°, the percentage of pressure equalization by the numerical simulation is 4% higher than wind-tunnel, so using a numerical method to evaluate wind loads on PER walls is practicable. But as the wind direction changes, there are some differences between the results of CFD simulations and wind tunnel test for wind directions from 45° to 135°, so the method of numerical model should to be modified.
3. The flow visualization of PER walls by water table
The flow visualization of PER walls by water table is similar to the results of wind-tunnel. At about 75° of wind directions visualization shows a larger circulation, indicating a large pressure difference across the rain screen may exist. Therefore water table can be used to observe the flow phenomenon of PER walls efficiently.

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