Flow Measurement in Fluid Channel using Unilateral and Bilateral RMS Cilia Array
In this study, to observe the fluid flow and particle behavior caused by the motion of the RMS cilia array, unilateral cilia array (UCA) and bilateral cilia array (BCA) channels were constructed, and the fluid flow was measured by applying two types of magnetic fields (strike and rotating magnetic fields). First, the same acrylic channel was used to measure the RMS cilia array motion, and both ends of the channel were opened (Figure. 1B(vii)). The channel was placed in the center of a 300 mm × 16 mm × 50 mm acrylic tank so that the channel was not affected by the tank wall as much as possible, and the channel was filled with 70 % glycerol solution (Figure. 2D).
First, in the UCA channel, a magnetized RMS cilia array was attached to one side of the channel and the channel was fixed in an acrylic tank. The 8-coil EMA system was used to apply the magnetic field for manipulation, and a CCD camera was used to observe the motion of the RMS cilia array and the resultant fluid flow. In particular, to observe the fluid flow, blue fluorescent polystyrene particles of size 5 μm were mixed with 70 % glycerol in a 1:4 volume ratio and 0.1 mL of this mixture was injected into the inlet of the channel. Subsequently, two types of magnetic fields (strike and rotating magnetic fields) were applied, and the fluid flow was observed by conducting four experiments for 100 s.
Second, BCA channels (symmetric and asymmetric) were prepared using the two types of RMS cilia arrays (Figure. 2A). A symmetric BCA channel was fabricated, in which two RMS cilia arrays magnetized in the same direction were symmetrically attached to the channel. The asymmetric BCA channel was fabricated by attaching two RMS cilia arrays magnetized in opposite directions to the channel. The BCA channel experiment was performed using the same method as that for the previously described UCA channel. Additionally, we applied a strike magnetic field with a frequency of 1–5 Hz and a rotating magnetic field with a frequency of 1–10 Hz.