一个大型水电站泻洪水雾输送与扩散的风洞模拟实验研究

根据大气环境物理模拟技术的原理和方法，在南京大学NJU大气环境风洞中，实施了一项风洞模型实验，模拟对象是一个地处河谷山地的水电站坝址，旨在研究建坝前后 的气流分布和变化以及水电站大坝泻洪水雾的输送与扩散范围。实验结果表明：拟建水电站大坝会对坝址区流场有一定的影响，但相当有限，垂直影响层高度约在1．5倍坝高；水平范围则在1km范围。而摄录的示踪水雾图象显示水雾散布的影响范围主要限于离站址0．5km范围内。 这些结果与已经进行的数值模拟的结果一致。这样,一方面用现代先进的数码摄像和照相技术显示了水电站大坝泻洪水雾输送扩散的模拟图象，另一方面通过气流测量的结果也为数值模式的进一步完善提供了实验依据。这些均表明了风洞模拟实验研究是一种有效和实用的技术手段。

Experimental Study in Wind Tunnel on Atmospheric Transport and Dispersion of the Spray Atomized from Flood Discharging by a Big Hydropower Station

On the basis of the principles and methods of the physical simulation for atmospheric environment, a model test has been carried out in NJU Atmospheric Environment Wind Tunnel. The subject is a domain of a hydropower station located in the mountains of a river valley is to study distributions and changes of the airflow before and after developing the station, The purpose is to learn the dispersion ranges of the spray atomized from flood discharging of the hydropower station. Experimental results show that there are some limited influences on the distribution of flow field. The height of the effective layer in vertical is 1.5 times as much as that of the dam and the horizontal range is less than one kilometer. Similarly the dispersion range of the spray atomized from flood discharging of the hydropower station is also limited to less than half kilometer. All of these results are consistent with the results by the numerical modelling. In the paper the dispersion patterns of the spray have been displayed by the advanced digital pickup camera. And on the other hand, the results of the measured airflow over the model provide an experimental basis for developing the numerical model. So it is demonstrated that the physical simulation in wind tunnel is an effective and practical technical approach.