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arXiv · 2512.14215

Turbulence enhancement of a fan array wind generator using geometric texturing and optimization-based control

Gengshou Cao·Tamir Shaqarin·Zhutao Jiang·Yutong Liu·Yiqing Li·Nan Gao·Xiaozhou He·Bernd R. Noack
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Abstract

Fan array wind generators (FAWG) are designed to generate a rich set of turbulent flows reminiscent of those found in natural environments. In this study, we experimentally investigate a square FAWG consisting of 10x10 individually controllable fans with 4 cm width and a maximum velocity of 17 m/s. The goal is to maximize the turbulence intensity in the test region. Two approaches for fan operation are investigated: first, geometric texturing of the duty cycle distribution, and second, maximization of the turbulence intensity at selected hot-wire sensors with particle-swarm optimization. We find that geometric texturing (specifically a checkerboard pattern) yields a robust, uniform turbulence field (Tu ~ 0.14) driven by jet interactions. Conversely, particle swarm optimization achieves higher local turbulence (Tu ~ 0.28) but significantly sacrifices spatial uniformity. This study underscores the trade-off between local maximization and global uniformity in active turbulence generation.

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Gengshou Cao, Tamir Shaqarin, Zhutao Jiang, Yutong Liu, Yiqing Li, Nan Gao, Xiaozhou He, Bernd R. Noack. 2025-12-16. Turbulence enhancement of a fan array wind generator using geometric texturing and optimization-based control. https://arxiv.org/abs/2512.14215

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