Riassunto analitico
Over the years aerodynamics has become one of the major factor that determines the F1 car performance and influences future developments. For that reason F1 teams invest a significant part of their budgets to improve wind tunnel tests and refine the information about the distribution of the flow around the car.
The flow field around the car is turbulent and, for its nature, it shows a wide population of rotating structures, the so-called turbulent eddies whose sizes and frequencies cover a wide range. Furthermore, turbulence introduce randomness that makes surprisingly difficult to define and observe elusive coherent structures that populate turbulent flow.
Particle image velocimetry (PIV) is an experimental technique that provides a powerful technical support for the analysis of the spatial and temporal evolution of the flow fields and, in the present work, it is used in conjunction with Proper orthogonal decomposition (POD), a mathematical technique whose purpose is to identify the most energetic structures established inside the flow field.
Aim of the present thesis is to use these techniques to carry out information about the organization in space of the flow and its evolution over time. Moreover a new method is proposed to detect the possible interaction between coherent structures using the cross correlation of the time coefficients obtained from the POD analysis. The proposed method is applied to different test cases and the results are discussed. In the end, using a synthetic flow field whose space and time evolution is known a priori, the strengths and weaknesses of this method are investigated.
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