Effect of a Wind Lens diffuser on turbulent flow

Keywords: Wind Lens, diffuser, turbulent flow, turbulence intensity


This article is aimed to measure the effect of a wind lens diffuser on turbulent flow. The study was conducted in the boundary layer wind tunnel of the Research Institute for Applied Mechanics at Kyushu University, Japan, between March and May 2019. A hot wire anemometer with a moving mechanism was used to conduct three tests. First, a characterization of the flow inside the wind tunnel was measured without the grid. Second, the turbulence intensity in the wind tunnel axis was measured this time with the grid in place. Third, the wind lens effect on the incident wind speed was determined at different levels of turbulence intensity. The wind speed in the tunnel without the turbulence grid was almost constant, approximately 9.6 m/s. When the grid was placed, a decreasing turbulence intensity was recorded in the axis of the wind tunnel, from 28.6 % at 500 mm from the grid to 5 % turbulence intensity at 3100 mm from the grid. When the effect of the wind lens was measured on the turbulent flow, wind speed increased up to 20 %. The wind lens proved suitable for wind turbines operating in turbulent flow, by increasing wind speed in all tests and generating a greater increase in the conditions with greater turbulence intensity.


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How to Cite
Richmond-Navarro, G., Casanova-Treto, P., & Hernández-Castro, F. (2021). Effect of a Wind Lens diffuser on turbulent flow. Uniciencia, 35(2), 1-15. https://doi.org/10.15359/ru.35-2.7
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