Onset Velocity Profiles Evolution in Microchannels

The present microfluidic study is emphasizing the flow behavior within a Y shape micro-bifurcation in two similar flow configurations. We report here a numerical and experimental investigation on the velocity profiles evolution and secondary flows, manifested at different Reynolds numbers (Re) and for two different boundary conditions. The experiments are performed using special designed setup based on optical microscopic devices. With this setup, direct visualizations and quantitative measurements of the path-lines are obtained. A Micro-PIV measurement system is used to obtain velocity profiles distributions in a spatial evolution in the main flows domains. The experimental data is compared with numerical simulations performed with commercial computational code FLUENT in a 3D geometry with the same dimensions as the experimental one. The numerical flow patterns are found to be in good agreement with the experimental manifestations.

Authors:

• Cătălin Mărculescu
• Andrei Avram
• Cătălin Pârvulescu
• Marioara Avram
• Cătălin Mihai Bălan

Keywords:

• Micro-PIV
• numerical investigations
• secondary flows
• velocity profiles.

References:

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