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为探究双曲冷却塔表面的三维绕流特性以及空间相关性,以某大型冷却塔为例进行刚体模型同步测压风洞试验,对表面平均和脉动风压分布以及环向和子午向的相关性进行了分析。研究发现,冷却塔的长细比较小,上下端均存在明显的三维绕流特性,并以塔筒上端尤为显著;端部效应主要表现在侧风区平均风压幅值下降、脉动风压激增、平均和脉动风压幅值最大点的后移以及风压环向相关性减弱。风压的环向相关性可以分为两个区域:“相关区域”(0≤|θ|≤100)和“非相关区域”(100°≤|θ|≤180°),其子午向相关性可以分为三个区域:“强相关区”(0°≤|θ|≤100°)、“弱相关区”(100°≤|θ|≤150°)以及“中等相关区”(150°≤|θ|≤180°);这使得冷却塔表面风压的双向(空间)相关性只存在于0°≤|θ|≤100°范围内。另外,在迎风点和侧风点,平均风压和脉动风压基本同时达到幅值的峰值,并且在环向和子午向存在极高的相关性,这都将显著增加风压分布的环向不均匀性以及风致结构响应。
In order to explore the three-dimensional flow around the hyperbolic cooling tower and its spatial correlation, a large-scale cooling tower was taken as an example to simulate the rigid-body model synchronous pressure wind tunnel test. The distribution of surface mean and fluctuating wind pressure and the relationship between the toroidal and meridional Sexuality was analyzed. The results show that the slenderness of the cooling tower is small, and obvious three-dimensional flow around the upper and lower ends of the cooling tower is obvious, especially in the upper end of the tower. The end effect is mainly manifested in that the mean wind pressure amplitude decreases and the fluctuating wind pressure increases , The backward of the maximum point of the average and fluctuating wind pressure amplitude and the weakening of the wind pressure ring direction. The toroidal correlation of wind pressure can be divided into two regions: “related region ” (0≤ | θ | ≤100) and “unrelated region” (100 ° ≤ | θ | ≤180 °) The meridional correlation can be divided into three regions: “strongly correlated region ” (0 ° ≤ | θ | ≤100 °), “weakly related region” (100 ° ≤ | θ | ≤150 °) “Medium correlation zone” (150 ° ≤ | θ | ≤ 180 °); this results in a bidirectional (spatial) dependence of the surface wind pressure on the tower only in the range of 0 ° ≤ | θ | ≤100 °. In addition, mean wind pressure and fluctuating wind pressure peak at both the windward and lateral winds at substantially the same time, and there is an extremely high correlation in the toroidal and meridional directions, which will significantly increase the toroidal wind direction distribution Inhomogeneity and wind structure response.