Strut-braced wings have recently garnered renewed interest in the aerospace industry due to their potential to improve aerodynamic efficiency and reduce structural weight. However, current Computational Fluid Dynamics (CFD) software tools face significant challenges in accura
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Strut-braced wings have recently garnered renewed interest in the aerospace industry due to their potential to improve aerodynamic efficiency and reduce structural weight. However, current Computational Fluid Dynamics (CFD) software tools face significant challenges in accurately predicting the unsteady flow phenomena associated with such designs, particularly in junction flow dynamics. This thesis aims to validate the capabilities of a Lattice Boltzmann Method (LBM) solver in predicting both the aerodynamic and aeroacoustic features of a model strut-braced wing. To achieve this, a series of wind tunnel tests were conducted to provide experimental data for comparison with the CFD results. Results showed good agreement between numerical and experimental steady measurements. The numerical solver could predict correct surface pressure distributions and a correct pressure coefficient was attainable for an adjusted angle of attack. Furthermore, the numerical method matched wake rake results to a high degree. However, the CFD transitional model was less sensitive to the transition strips, incorrectly assuming untripped flow at the wing surface when in the wind tunnel, the trips successfully transitioned the boundary layer.
The numerical model struggled to capture the unsteady phenomena due to the junction flow at the strut wing intersection. Unsteady pressure measurements showed that the LBM solver overpredicted surface pressure fluctuations near the junction region, affecting the accuracy of the acoustic analogy employed by the CFD software and, ultimately, misrepresenting the junction as the primary acoustic noise source. As such, the solver in question struggles to accurately predict the noise of a strut-braced wing. Moreover, further investigation must be done to improve the wind tunnel anechoic performance, as the tunnel diffusor and test section were identified as the dominant noise sources, thus hindering the analysis.