This work contains an acceptable solution to the most practical interest to reduce the internal pressure load variations acting on closed envelops (i.e., inner building walls, fairing of rocket, and missile payloads) under gusty wind conditions. To simulate the gusty wind conditions (i.e., tangential unsteady flow condition), an experimental setup of a wind tunnel with a sinusoidal gust generating mechanism has been established in IDR of the Universidad Politécnica de Madrid (IDR/UPM), Spain. The wind tunnel has been equipped with an air reservoir with vent holes. The pressure jumps shown across the vent holes are studied as a function of sinusoidal gust frequency, volume of the air reservoir, and vent hole size. A theoretical model (based on the mass conservation equation and polytropic law gas evolution) has been proposed to predict the pressure jumps and variations under gusty wind conditions. At the end of the work, theoretical and experimental results have been studied and compared. The relationship between pressure loss coefficient and flow coefficient under unsteady flow conditions has been evaluated.

中文翻译：

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阵风条件下围墙内压力载荷的实验与理论研究

这项工作包含一个可接受的解决方案，以减少阵风条件下作用在封闭包络（即建筑物内壁、火箭整流罩和导弹有效载荷）上的内部压力载荷变化。为了模拟阵风条件（即切向非定常流动条件），在西班牙马德里理工大学（IDR/UPM）的IDR建立了具有正弦阵风产生机制的风洞实验装置。风洞配备了带通风孔的储气罐。作为正弦阵风频率、储气罐体积和通风孔尺寸的函数，研究了通风孔上显示的压力跳跃。已经提出了一种理论模型（基于质量守恒方程和多方定律气体演化）来预测阵风条件下的压力跳跃和变化。在工作结束时，对理论和实验结果进行了研究和比较。压力损失系数的关系并评估了非稳态流动条件下的流量系数。