Flow and Noise Control of a Cylinder with Annular Plates

Faezeh Eydi

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arXiv · 2502.16676

Flow and Noise Control of a Cylinder with Annular Plates

Faezeh Eydi

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Abstract

With the growing demand for electricity and increasing interest in renewable energy, wind turbine noise pollution has become a more pressing issue. Aerodynamic noise not only impacts human well-being but also affects wildlife. This study investigates the aeroacoustics and aerodynamics of a two-dimensional circular cylinder exposed to turbulent flow at a fixed Reynolds number of 22,000. A key novelty of this research is the introduction of a passive control technique, achieved by designing a structure with two thin annular plates positioned around the cylinder in the circumferential space. The numerical analysis is conducted using unsteady Reynolds-averaged Navier-Stokes (URANS) methods in combination with the Ffowcs Williams and Hawkings (FW-H) acoustic analogy. The control assessments reveal substantial performance improvements, with reductions of 89.46% in the mean drag coefficient and 86.6% in the Strouhal number for the modified cylinder. From an acoustic perspective, the passive control method achieves a maximum noise reduction of 39 dB, with a notable drag reduction of 50.62% in a specific case. This innovative design offers a highly efficient and cost-effective solution for noise reduction and wake control in wind turbine applications. Its eco-friendly nature, ease of implementation, and maintenance-free operation make it a promising approach for enhancing wind turbine performance without additional energy consumption.

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Faezeh Eydi. 2025-02-23. Flow and Noise Control of a Cylinder with Annular Plates. https://arxiv.org/abs/2502.16676

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