Blockage Effects in Wind Tunnel Experiments of Turbulent Wakes: A Numerical Study
Gianluca PORPORA, Andrea PALUMBO
Abstract. In many industrial applications, turbulent flow past bluff bodies separates, causing aerodynamic forces unsteadiness, structural vibrations, and noise. Wind tunnel experiments are commonly used to study wake dynamics, evaluate aerodynamic coefficients and perform spectral analyses. However, wind tunnel walls may significantly alter the wake topology, thereby leading to biased measurements. Predictive formulae for the effect of confinement are mainly available for simple bodies, such as circular and square cylinders. This study investigates the influence of wall confinement on the turbulent wake behind a missile-shaped airfoil using unsteady Reynolds-averaged Navier–Stokes (URANS) simulations. The analysis is performed at moderate Reynolds numbers and for various blockage ratios. Results show that drag, lift fluctuations, and shedding frequency all increase monotonically with blockage ratio. These findings extend previous observations on laminar confined wakes to turbulent bluff-body wakes, underscoring the importance of designing proper wind tunnel experiments.
Keywords
Computational Fluid Dynamics, Separated Flows, Wind Tunnel Blockage
Published online 7/20/2026, 6 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Gianluca PORPORA, Andrea PALUMBO, Blockage Effects in Wind Tunnel Experiments of Turbulent Wakes: A Numerical Study, Materials Research Proceedings, Vol. 69, pp 227-232, 2026
DOI: https://doi.org/10.21741/9781644904251-40
The article was published as article 40 of the book CEAS – AIDAA Conference 2025
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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