The carbon nanotube based micro bubble generator in micro channel with dynamic fluid

Based on the previous study of micro bubble generation using carbon nanotube heating elements with uW power input in static droplet of water, the dynamic characteristic of micro bubble generated by CNTs heater draw us much attention. In this summary, the micro bubble transportation, diameter control in micro channel and the departure of micro bubble from CNTs heater by pulse current stimulation in water tank will be presented. On the one hand, PDMS, after fabricating micro channel on it, will be bonded to the silicon substrate by oxygen plasma to form micro channel device. In our research, we could observe that the movement of vapor bubble along the micro channel by pulse flow or constant flow. The power consumption for bubble generation in micro channel is relative higher than that in static droplet of water, but it keeps staying around 275 uW. Furthermore we also use the injected cool water to control the diameter of the micro bubble. On the other hand, from micro bubble departure in water tank experiment, we observe that the micro bubble has shake response by pulse current input on the CNTs heater, which accelerate the departure of micro bubble. With low power consumption, dynamic transportation and controDable diameter, the micro bubble generated by CNTs heater in micro channel offers a promising future in lots of application, e.g., micro manipulation and micro transportation. ©2008 IEEE.