Fluid Mechanics & Aerodynamics

Fluid Mechanics & Aerodynamics

Experimental assessment of the Performance of Twisted Wind Flow Simulator in a Small-Scale Boundary Layer Wind Tunnel Using a 5-Hole Probe

Document Type : Original Article

Authors
ali Zadehmohammad 1
Mahdi Rastgari 1
Mohammad Hojaji 2
seyed Jalil Hosseini 3
1 Master's student, Department of Civil Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran
2 Assistant Professor, Department of Mechanical Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran
3 Assistant Professor, Department of Civil Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran
Abstract
Given the destructive effects of storms and the importance of their simulation and investigation, this study simulates a specific type of twisted atmospheric boundary layer wind flow in a boundary layer wind tunnel. Considering the high cost and energy consumption of simulation and testing in large-scale tunnels, the aim of this study was to reduce the cost and energy waste by using a small-scale wind tunnel. To assessment the twisted wind flow, two types of simulation systems representing high and extreme twisting of the wind flow were used. The flow conditions were evaluated using a flow observation system, a laboratory hot-wire sensor, and a 5-hole probe capable of measuring parameters such as velocity, turbulence intensity, and twist angle of the flow. Finally, by studying and comparing the profiles of twist angle, velocity, and flow turbulence with previous references, it was shown that by making some changes in the simulator system, a simulation with reasonable accuracy can be performed in a small-scale wind tunnel. So the difference between the velocity and turbulence profiles measured in this study and those reported in previous references was less than 5%. Additionally, for simulators with maximum guidance angles of 15 and 30 degrees, the resulting flow twist angles were 12 and 20 degrees, respectively, with a deviation of less than 2 degrees compared to previous references. Therefore, it can be concluded that the simulation conducted in this study shows a strong agreement with prior simulations that utilized large-scale wind tunnels.
Keywords
Wind Flow Wind Tunnel Twisted Wind Flow Observation 5
Hole Probe

Smiley face

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Fluid Mechanics & Aerodynamics
Volume 14, Issue 1 - Serial Number 35
Spring and summer
September 2025
Pages 63-77

  • Receive Date 30 April 2025
  • Revise Date 23 July 2025
  • Accept Date 20 August 2025
  • Publish Date 23 August 2025