A novel micropump is proposed comprising two ferrofluidic plugs contained within a circular poly(methyl methacrylate) (PMMA) microchannel and a permanent magnet positioned beneath one of the plugs and driven by a rotating stepping motor. The ferrofluidic plugs are immiscible with the sample fluid. Thus, as the stepping motor rotates, the sample trapped between the two plugs is driven through the circular microchannel and exits the pump via the outlet diffuser. Meanwhile, more sample fluid is drawn into the microchannel on the inlet side. As a result, a continuous pumping effect is achieved. It is shown that the flow rate in the proposed device can be easily controlled by adjusting the rotational velocity of the stepping motor. In addition, for a constant motor velocity, the flow rate can be improved by increasing the circular channel width. The experimental results show that a maximum flow rate of 93 μl/min is obtained given a channel width of 1000 μm and a rotational velocity of 8 rpm. In addition, it is shown that the pump is capable of developing a maximum pressure head of 75mm water (0.66 kPa) with channel width of 500 μm.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)