Simultaneous Measurements of 3D Flow Structures and Wall Shear Stresses Using Digital Holographic Microscopy

Johns Hopkins University, Baltimore MD

Investigators

Abstract

PROPOSAL NO.: CTS-0625571 PRINCIPAL INVESTIGATOR: JOSEPH KATZ INSTITUTION: JOHNS HOPKINS UNIVERSITY Intellectual Merit: The investigators propose using a novel digital holographic method to examine flow features near the wall in canonical turbulent boundary layers. This experimental technique is original and promises groundbreaking results in the understanding of turbulent wall bounded flows. The panel was very impressed with the proposal and felt the development of the high resolution digital holographic microscopy (DHM) would be a valuable measurement tool for turbulence. The high spatial resolution of the technique as well has the relatively large measurement region provides the ability to obtain the instantaneous distribution of velocity, wall shear stress as well as near wall flow structures. Tracking the same group of particles in pairs of velocity fields recorded at different times also provides the material acceleration. The PIs have been extremely productive and innovative in the past and the preliminary results using the technique are convincing. Broader Impacts: Successful completion of this research would have a substantial impact in the field of turbulence by advancing an emerging, high spatial resolution measurement tool for turbulence, as well as providing a valuable data set on canonical boundary layers. This work will be used in an educational plan by involving two graduate students as well as senior high-school students from the Baltimore Polytechnic Institute. Details of the technique will also be made available to the community.