Abstract Combined with the negative pressure zone outside the duct, a new method based on the converging-diverging tube using for speeding up the low-grade wind is proposed in this paper. Firstly, a 3D CFD model of the converging-diverging air duct is developed, and the validation of the numerical model is also shown by comparing the experimental and numerical data. Secondly, based on the method of velocity stratification analysis at the air duct throat, the effect of the outlet angle on the speed increase is studied, and the mechanism of the negative pressure zone on changes to the wind speed is also analyzed and discussed. The air duct geometry was optimized, and the simulation study results were verified through experimental tests with a prototype duct and a wind tunnel. The results show that air ducts can significantly focus and increase wind speeds, offering insight for the future use low-speed winds for electricity generation.

中文翻译：

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发散角对低速加速风管内流动行为的影响

摘要 结合风管外的负压区，提出了一种基于聚散管加速低级风的新方法。首先，建立了收敛-发散风管的3D CFD模型，并通过比较实验和数值数据来验证数值模型的有效性。其次，基于风管喉部速度分层分析方法，研究了出风角对风速增加的影响，并分析讨论了负压区对风速变化的影响机理。优化了风道几何形状，并通过原型风道和风洞的实验测试验证了模拟研究结果。