The aim of this paper is to provide a contribution to algorithms for the numerical simulation of the atmospheric boundary layer (ABL) in short test section wind tunnel, with the lowest pressure loss possible, for large Re, similar to the high values observed in nature. Different turbulent models have been examined for their relative suitability for the atmospheric boundary layer airflow with and without the implementation of buoyancy effects with modified turbulence model constants for the atmosphere. Validation of turbulent models through comparison with wind tunnel experiments is essential for practical applications. It has been observed that the k-ε model is most suitable tool for generation of an ABL in short-chamber wind tunnel. A comparison has been made with the available experimental data, from literature, and the predicted CFD values are very close to the corresponding experimental measurements. The simulation results show the importance of turbulence model constant (Cµ), the non-uniform velocity and turbulence intensity profiles. Also, the significance of y+ for consistent assessment is confirmed. However, it has been found that the buoyancy force makes significant change in boundary layer thickness without a major impact on computation time.
Yassen El-Sayed Yassen,
Ahmed Sharaf Abdelhamed,
CFD Modeling of the Atmospheric Boundary Layer in Short Test Section Wind Tunnel, American Journal of Aerospace Engineering. Special Issue: Hands-on Learning Technique for Multidisciplinary Engineering Education.
Vol. 2, No. 1-1,
2015, pp. 38-46.
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