Wednesday, February 26, 2020 | 3:45PM | Yost 306

Speaker: Dr. Bryan Schmidt, MAE, CWRU

Title: Measuring Velocity in Turbulent Flows: Moving Beyond Particle Image Velocimetry

Abstract

Turbulent flows are all around us: from the wake behind the wind turbine outside of Veale, to the combustors inside the gas turbine engines powering the airplanes flying overhead, to the boundary layers on the hulls of ships crossing Lake Erie. And yet, turbulence remains one of the most challenging phenomena to study in all of physics, and it is notoriously difficult to model. Accurate, spatially resolved experimental measurements are crucial to improve our understanding and models of turbulence. For the past thirty years, particle image velocimetry (PIV) has been the workhorse for making these  measurements.

Recently, new methods have been developed which address some of the shortcomings of PIV image processing, simultaneously improving accuracy, spatial resolution, and flexibility. One of these methods is wavelet-based optical flow velocimetry (wOFV). wOFV adapts optical flow, a motion-tracking technique in computer vision, to fluid flow images, using sparse wavelet representations of the velocity field to close the inverse problem of optical flow. Physically sound regularization is applied by influencing directional derivatives of the velocity field in the wavelet domain. In this seminar I will  highlight some recent developments in the wOFV method as well as outline avenues for future advancements.