Main results of the analysis of the HOMER Lagrangian Particle Tracking and Data Assimilation database

Abstract

In this work, we extend the analysis of Lagrangian Particle Tracking (LPT) and Data Assimilation (DA) algorithms, presented at the ISPIV21 conference, to the case of a turbulent wall-bounded flow interacting with a moving panel. The work is conducted within the European project HOMER and the data is processed by the partners of the project consortium. A synthetic experiment is performed that reproduces the air flow around a cylinder in ground effect, whereby a flexible panel is placed undergoing periodic oscillations. The database comprises two different panel's materials, namely metal and rubber, different marker densities on the panel’s surface and different concentrations of tracer particles in the flow. Images of the flow tracers and of the surface markers are acquired either with a fourcamera volumetric imaging setup or with a dual setup composed of four LPT cameras and two Digital Image Correlation (DIC) cameras. Additionally, three image acquisition modes are simulated, namely time-resolved, twopulse and four-pulse. The data are analyzed in terms of percentages of correctly reconstructed, missed and ghost particles, errors of the measured particles’ positions, velocities and accelerations (LPT analysis) and errors of the reconstructed flow fields, panel’s positions and surface pressures (DA analysis).