Pressure field estimation from particle image velocimetry data

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2018
Günaydınoğlu, Erkan
In this thesis, a methodology is proposed to estimate pressure fields from particle image velocimetry measurements. The methodology uses the velocity fields acquired from the experiments as initial and boundary condition and employs Semi-Implicit Method for Pressure Linked Equations algorithm to solve governing equations. Finite volume method is employed with high order discretization scheme for solution of steady and transient flows. The methodology is validated with theoretical flows and further verified with conventional pressure measurement tools. The sensitivity of the methodology to the velocity field error is also assessed. Method estimates the pressure fields exactly for error free velocity fields. Moreover, method can correct the flow-fields to accurate values even with extremely high experimental uncertainties and errors. The methodology is further employed on a flapping airfoil experiment and capability of pressure estimation is tested for highly vortical flows. The proposed methodology offers a reliable, non-intrusive, global pressure measurements simultaneously with the corresponding velocity fields. Due to the error-correcting nature, it could also be used for quantifying the uncertainties of experimental systems or calibrating numerical tools.

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Citation Formats
E. Günaydınoğlu, “Pressure field estimation from particle image velocimetry data,” Ph.D. - Doctoral Program, Middle East Technical University, 2018.