基于多尺度数值同化模式的泄洪雾化对天气环境影响的数值模拟研究

Numerical simulation of the effects of flood discharge atomization on weather environment based on multi-scale numerical assimilation model

水电站局地天气要素的变化一直是泄洪雾化影响评价的重要组成部分,如何实现水电站局地气象场的高精度数值模拟,已成为泄洪雾化数值模拟方面亟需解决的重要问题。应用数值天气预报模式,采用松弛同化技术将泄洪时段的水舌风、温度、相对湿度、压强等物理参数,同化到数值天气预报模式的背景场中,并耦合小尺度诊断模型进行动力降尺度处理,首次将坝区物理场的水平分辨率提高到40 m,得到小尺度下锦屏一级水电站泄洪时段天气要素的变化情况和影响范围,为评价泄洪雾化对天气环境的影响提供研究基础。

The variation of local weather factors of hydropower stations has always been an important part of flood discharge atomization impact assessment.How to realize the high-precision numerical simulation of local meteorological field of hydropower stations has become a major issue to address in the numerical simu⁃lation of flood discharge atomization.In this paper,numerical weather forecast model and the nudging assim⁃ilation method are used to assimilate physical data such as nappe wind,temperature,relative humidity,and pressure into the background field of numerical weather forecast model.Also,the dynamic downscaling has been performed by coupling the small-scale diagnostic model.It is the first time that the horizontal res⁃olution of the physical field in the dam area has been raised to 40 m.The variation and influence range of local weather factors in the flood discharge period in JingpingⅠHydropower Station are obtained on a small scale,which provides a research basis for a further evaluation on the impact of flood discharge atomi⁃zation on weather environment.