Improvements in full field techniques for the measurement, simulation and analysis of confined flows in complex geometry

Identifier:  TDX:278

Handle: https://hdl.handle.net/20.500.11797/TDX278

Authors:  Usera Velasco, Gabriel

Abstract:
This thesis deals with the improvement of techniques for the detailed analysis, experimental measurement and numerical simulation of flows confined within complex geometry. Interrogation algorithms for time resolved PIV were designed and implemented. Special attention was given to the treatment of the near wall portions of the images to ensure appropriate resolution of the boundary layer by proper placement of the displacement vector when the interrogation area overlaps the image boundary. A 3D finite volume solver for the Navier Stokes equations was created. This numerical model works with block structured grids and sliding interfaces, allowing the treatment of rather complex geometries. This solver has been fully parallelised using OpenMP. The set of techniques was completed devising a novel conditional sampling method based on fuzzy clustering for the analysis of large scale dynamics in turbulent flows. A set of ensemble averages is produced and the time evolution of the flow can be analysed through the most probable sequence in time of the conditionally sampled averages. A case study was selected to drive the evolution of these techniques, concerning the flow inside a printed circuit board (PCB) enclosure. <br/>Keywords: PIV, Finite Volume, Fuzzy Clustering, confined flows