摘要

A methodology for improved sensor-based velocity field estimation from experimental data in bluff-body wakes is presented and illustrated for the turbulent wake of a wall-mounted square-base pyramid. The sensors monitor the local surface pressure, while the velocity field is measured with planar, time-resolved stereoscopic PIV. Starting from the extended proper orthogonal decomposition technique, key improvements of the spatio-temporal resolution of the strongly modulated shedding include: (1) exploiting the guaranteed orthogonality of the velocity expansion modes; (2) using explicit modal cross-correlations between velocity and pressure fields; (3) determining objectively sensorsignal time delays; and (4) benefiting from symmetry considerations. Combined, these filtering operations yield a near-optimal estimation from surface pressure signals. It is shown that the mean-field paraboloid is better rendered and the residual of the estimated coherent kinetic energy is 30% - 50% smaller than with previously proposed estimation methods.