This thesis investigates the aerodynamic performance and evolution of turbulent jet flows from two distinct car cabin vents from G09 and G07LCI models of BMW. The former represents a conventional design, while the latter represents an innovative hidden concept. Large Eddy Simulations (LES) are employed to simulate the jet flows. The study aims to characterize the dynamics of jet flows, identify coherent structures within them, and evaluate their impact on climate control performance and passenger comfort. The simulation setup was inspired by a smoke rig test bench, with a novel automated mesh refinement technique ensuring accurate resolution of jet flow development. Mean value analyses revealed significant discrepancies between the two vent jet flows. The G09 vent exhibited a more gradual decline in peak velocities and reduced turbulence downstream, while the G07LCI vent demonstrated higher turbulence levels in the vicinity of the outlet, yet exhibited a faster decay in turbulence downstream, particularly in the absence of a cover aperture. Cross-spectral density analyses revealed that the G07LCI vent exhibited stronger correlations in velocity fluctuations, particularly near the outlet. Proper Orthogonal Decomposition (POD) was employed for the purpose of identifying coherent structures and analyzing contributions of the modes to turbulent kinetic energy (TKE). The results demonstrated that coherent structures were more pronounced in smaller regions within the near field, whereas they were less discernible but spanned larger areas within the far field. Furthermore, frequency analysis revealed that passenger-perceptible structures (below 10 Hz) contributed significantly to the overall turbulence, particularly within the far field. The G09 vent distributed a greater proportion of energy to higher frequencies, thereby reducing the likelihood of perceptible phenomena within the flow. This study underscores the potential of advanced simulation and decomposition techniques in analyzing vent jet flows and lays the groundwork for future research into optimizing vent designs to enhance passenger comfort. Further investigations are required to determine the presence of dominant coherent structures that may influence passenger perception.     «

This thesis investigates the aerodynamic performance and evolution of turbulent jet flows from two distinct car cabin vents from G09 and G07LCI models of BMW. The former represents a conventional design, while the latter represents an innovative hidden concept. Large Eddy Simulations (LES) are employed to simulate the jet flows. The study aims to characterize the dynamics of jet flows, identify coherent structures within them, and evaluate their impact on climate control performance and passenge...     »