Paper Number
RS27 

Session
Techniques and Methods: Rheometry & Spectroscopy/Microscopy

Title
FSVPy: A python-based package for fluorescent streak velocimetry (FSV)

Presentation Date and Time
October 12, 2022 (Wednesday) 2:30

Track / Room
Track 6 / Mayfair

Authors (Click on name to view author profile)

1. Lin, Han (Northwestern University, Chemical and Biological Engineering)
2. Blackwell, Brendan (Northwestern University, Department of Physics and Astronomy)
3. Driscoll, Michelle M. (Northwestern University, Physics)
4. Richards, Jeffrey J. (Northwestern University, Chemical and biological engineering)

Author and Affiliation Lines (in printed abstract book)
Han Lin¹, Brendan Blackwell², Michelle M. Driscoll² and Jeffrey J. Richards^1
1Chemical and Biological Engineering, Northwestern University, Evanston, IL 60208; ²Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208

Speaker / Presenter 
Richards, Jeffrey J.

Keywords
experimental methods; rheometry techniques; suspensions

Text of Abstract
In this work, we describe the extraction of quantitative velocimetry data from streaks generated by fluorescent tracers added to millifluidic channel flows. This category of velocimetry is called fluorescent streak velocimetry (FSV). We report two different methods for velocimetry using streak analysis. The first assumes unidirectional flow, where we calculate the local velocity using the ratio of streak length to the exposure time. The second is applied to more complicated flows, where we demonstrate that the variation in fluorescent intensity along the streak contour can be utilized to extract quantitative velocimetry data. We demonstrated the use of this code in a broad range of flow scenarios, first attaining 3D velocity fields for a both Newtonian and non-Newtonian fluids in unidirectional flow, then measuring more complex flow fields. The advantages of FSV over other commonly used techniques such as PIV and PTV are shorter run time and efficient encoding of information.