Augmenting PIV Temporal Resolution via Semi-Lagrangian Estimation of Velocity Fluctuations

This study introduces a convective velocity estimation method based on space-time correlations to enhance the temporal resolution of turbulent flow measurements using semi-Lagrangian techniques. The approach is evaluated using DNS data of a turbulent plane jet at \(Re = 10{,}000\) . Comparison between correlation-based convective velocity \(U_c\) and mean axial velocity \(U_m\) reveals significant differences, with \(U_c\) generally lower near the jet centreline and higher towards lateral edges. Spectral analysis demonstrates that \(U_c\) based advection yields improved predictions of the turbulence spectrum compared to \(U_m\) . Future work will explore scale-dependent convective velocities and their impact on reconstructed frequency spectra.