海岛微地形风洞试验研究

Wind Tunnel Test of Island Microtopography

海岛四周由于受海风影响较大,其风场特性处于不断变化中,准确了解海岛的风场特性是进行相关建设抗风设计的基础。然而,现行相关规范描述风场特性的数学模型通常仅适用于内陆平坦地形,尚不足以描述类似海岛地形的风环境。因此,采用风洞试验的方法对南澳岛上一个山谷内的风场特性进行了研究。研究结果表明:越靠近山谷中心,平均风速剖面与湍流强度剖面变化越大;主要风向来流下各测点的脉动风速功率谱与Von-Karman谱较为吻合。研究成果可为类似地形下的工程设计提供试验依据。

The island is greatly affected by the sea breeze,hence its wind field characteristics are constantly changing.Accurate understanding of its wind characteristics is the basis of wind resistance design for related construction.However,the existing mathema-tical models describing the characteristics of wind field are usually only suitable for inland flat terrain,which is not enough to describe the wind environment similar to island terrain.Therefore,the wind tunnel test method was used to study the wind field characteristics in a valley on Nan’ao Island.The results show that the closer to the center of the valley,the greater the variation of mean wind speed profile and turbulence intensity profile.The results show that the power spectrum of fluctuating wind speed at each measuring point under the main wind direction is in good agreement with the Von-Karman spectrum.The research results can provide experimental basis for similar engineering design.