INVESTIGATION OF WIND FLOW CHARACTERISTICS USING PASSIVE DEVICES IN BOUNDARY LAYER WIND TUNNEL

Authors

  • Miko Hadi Wijaya Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100 Kuala Lumpur, Malaysia
  • Sheikh Ahmad Zaki Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia: Jalan Sultan Yahya Petra, 54100 Kuala Lumpur, Malaysia.
  • Ahmad Faiz Mohammad Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100 Kuala Lumpur, Malaysia
  • Nurizzatul Atikha Rahmat Faculty of Mechanical and Automotive Engineering Technology, Universiti Malaysia Pahang Al-Sultan Abdullah, 26600 Pekan, Pahang, Malaysia
  • Nor’azizi Othman Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100 Kuala Lumpur, Malaysia

DOI:

https://doi.org/10.11113/jtse.v11.230

Keywords:

wind tunnel; boundary layer; surface roughness

Abstract

Atmospheric boundary layer (ABL) flow can be generated in an open-loop boundary layer wind tunnel (BLWT) to simulate a realistic rough-wall condition imposed on the natural wind. An open-loop BLWT experiment is performed in this work using a wall barrier and roughness elements as passive devices to create a rough-wall condition and reproduce a realistic neutral ABL flow. The roughness elements used are homogeneous cubic blocks with a side length of 25 mm arranged in a staggered layout at 12.5% packing density. Wind velocity data is measured in the upstream test section of the BLWT using a hot-wire anemometer (HWA) to obtain the wind velocity profiles, i.e., mean wind velocity, standard deviation, and skewness. The height z was measured from z = 7 mm from the test section floor to z = 800 mm. The mean vertical velocity profile of the rough wall indicates a significant decrease within the height interval of z/zref < 1.0 due to the surface roughness. Additionally, the normalized mean wind velocity is approaching unity at z/zref = 1 with the rough wall, whereas the smooth wall (no roughness elements) is observed at z/zref = 0.1. Moreover, the standard deviation profile of the rough wall shows higher values in the near-wall region (z/zref ≤ 0.4), suggesting a higher level of turbulence in the wind flow due to surface roughness. Finally, the rough wall skewness profile is left-skewed, suggesting a non-Gaussian feature. The study found that roughness parameters affect vertical velocity profiles and create realistic atmospheric boundary layer flows.

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Published

2024-05-30

How to Cite

Wijaya , M. H., Zaki , S. A., Mohammad , A. F., Rahmat , N. A., & Othman, N. (2024). INVESTIGATION OF WIND FLOW CHARACTERISTICS USING PASSIVE DEVICES IN BOUNDARY LAYER WIND TUNNEL . Journal of Transport System Engineering, 11(1), 70–73. https://doi.org/10.11113/jtse.v11.230

Issue

Section

Transport System Engineering

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