We show that the performance of a streaming-potential based microfluidic energy conversion system can be strongly enhanced by the use of two phase flow. Injection of gas bubbles into a liquid-filled channel increases both the maximum output power and the energy conversion efficiency. In single-phase systems the internal conduction current induced by the streaming potential limits the output power, whereas in a two-phase system the bubbles reduce this current and increase the power. In our system the addition of bubbles enhanced the maximum output power of the system by a factor of 74 and the efficiency of the system by a factor of 163 compared with single phase flow.
Xie, Y., Sherwood, J. D., Shui, L., van den Berg, A., & Eijkel, J. C. T. (2011). Strong enhancement of straeming current power by application of two phase flow. Lab on a chip, 11(23), 4006-4011. https://doi.org/10.1039/c1lc20423h