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Visualization of Flow Regimes in Symmetric Microchannel in Case of Different Inlet Flowrate Ratios for Fixed Outlet Reynolds Number


An experimental investigation of flow pattern regimes and mixing inside a T-type microchannel for different inlet flowrate ratios was carried out. Seven flow pattern regimes were obtained experimentally. Partial penetration of the flow into the opposite input channel with occurrence of one vortex was shown by Rahimi et al. [8]. We experimentally demonstrate arising of two vortex structures rotating about their axes in the case of partial penetration of the flow into the opposite input channel. In addition, we reveal appearance of periodic waviness streaks, absent in previous works. We also investigated the evolution of a transparent periodic vortex structure inside the outlet microchannel. It is a very slow periodic process. The mixing efficiency for all flow regimes is estimated. A maximum mixing of 0.87 is achieved for the streaks and unsteady regimes. We also discover that the biggest mixing efficiency is equal to 0.67, reached at \(R=0.25\) and a low outlet Reynolds number Re = 47.

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The work was supported by the Russian Science Foundation (project no. 19-79-10217).

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Correspondence to A. Yu. Kravtsova.

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Kravtsova, A.Y. Visualization of Flow Regimes in Symmetric Microchannel in Case of Different Inlet Flowrate Ratios for Fixed Outlet Reynolds Number. J. Engin. Thermophys. 29, 612–617 (2020).

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