Fig 1.
3D images of the SHM devices used in the experiments.
(A) Positive forward (B) Positive reverse (C) Negative forward (D) Negative reverse. Size of scale bar is 100 μm. Detailed dimension of the structure is displayed in magnified pictures on the right of each image.
Fig 2.
Mixing of DI water and fluorescein solution.
In blank (A), and SHM device with forward (B) and reverse (C) flow.
Fig 3.
Normalized fluorescence intensity across the microchannel after each cycle from 1 to 5.
(A) Positive forward (B) Positive reverse (C) Negative forward (D) Negative reverse (E) Negative reverse with full scale of fluorescence intensity.
Fig 4.
Numerical simulation results of the SHM devices.
Red and blue color indicates fluorescein and DI, respectively. The white color code represents complete mixing. (A) Top view images obtained from the 3D simulation of the SHM up to 2.5 cycles (the width of the microchannels in the images are magnified 2 times for better observation) (B) Top view images of simulated flow at the entrance of the first cycle (C-D) Cross sectional images and color intensity of each fluid in the microchannel (C) After first cycle (D) After third cycle. The color legends present fluorescence dye (red) and DI (blue) concentrations.
Fig 5.
Numerical simulation of the fluid behavior at SHM entrances.
(A) Positive forward (B) Negative forward (C) Shallow negative forward. Arrows indicate relative vorticity of the fluids regarding x and z axis of the channel. (D-E) Cross sectional images and color intensity of each fluid in the microchannel. (D) After first cycle of shallow negative. (E) After third cycle of shallow negative. The color legends present concentrations of fluorescence dye (red) and DI (blue).
Fig 6.
Cross-sectional velocity vector plots at SHM entrances.
(A) Positive forward (B) Negative forward (C) Shallow negative forward. Arrows indicate relative velocity of the fluids regarding y and z axis of the channel. Fluidic velocity in the positive pattern is seven and two times larger than the negative and shallow negative pattern, respectively, when the size of the arrow in simulation is the same due to scale factor difference.
Fig 7.
Normalized fluorescence intensity across the microchannel in viscous fluid test.
after each cycle from 1 to 10. (A) 10% Positive forward, (B) 10% Negative forward, (C) 25% Positive forward, (D) 25% Negative forward.