Assessment of Turbulence Model Assumptions Through Comparative Analysis of a Typical Turbulent Flow Field

This study evaluated the influence and practical implications of turbulence-model assumptions for a representative transonic RAE2822 airfoil case using computational fluid dynamics. The workflow established a valid high-Re baseline solution through geometry preparation, construction of the external computational domain, near-wall inflation, far-field boundary conditions, and the standard k–ε model with standard wall functions. The y⁺ assessment required adjustment of the first-layer height and inflation settings until the reported values were within the stated range of 30–300. A second mesh with approximately twice the cell count produced only small differences in aerodynamic coefficients and pressure distributions, supporting the reported grid-independent solution. Comparison with the provided experimental data captured the principal pressure and aerodynamic trends with acceptable agreement, while minor deviations were consistent with the stated limitations of the standard k–ε model. The Mach and Reynolds number matching procedure further aligned the CFD setup with the target experimental conditions. Overall, the study demonstrates the importance of mesh quality, near-wall resolution, similarity conditions, and experimental comparison when assessing turbulence-modelling assumptions in transonic CFD. The refined mesh increased computational time but remained manageable within the stated hardware and license constraints.

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