Title :
Comparative Study of Size Effect of Micro Bubble Dynamics by Sub-100 Microsecond and Millisecond Pulse Heating
Author :
Pak Kin Leung ; Deng, Peigang ; Lee, Yi-Kuen
Author_Institution :
Dept. of Mech. Eng., Hong Kong Univ. of Sci. & Technol.
Abstract :
Two groups of boiling patterns generated by a set of different sizes of micro bubble actuators were observed using new stroboscopic video microscopy. Above the critical heater size, bubble collapse as an oblate vapor film; while the other case, single spherical bubble was observed. The critical sizes are 1-3 mum and 5-10 mum for the heating pulse widths of 40 mus and 1.66 ms, respectively. A simple model based on thermal diffusion length was successfully employed to predict the critical size of bubble actuators
Keywords :
boiling; bubbles; microactuators; microfluidics; stroboscopes; thermal diffusion; 1.66 ms; 40 mus; boiling pattern; bubble actuator critical size; bubble collapse; critical heater size; heating pulse width; microbubble actuators; microbubble dynamics; microsecond pulse heating; millisecond pulse heating; size effect; stroboscopic video microscopy; thermal diffusion length; Actuators; Heat engines; Microelectromechanical devices; Micropumps; Microscopy; Predictive models; Pulse generation; Space vector pulse width modulation; Systems engineering and theory; Water heating; boiling pattern; bubble dynamics; homogeneous boiling; micro bubble actuator; size effect;
Conference_Titel :
Nano/Micro Engineered and Molecular Systems, 2006. NEMS '06. 1st IEEE International Conference on
Conference_Location :
Zhuhai
Print_ISBN :
1-4244-0139-9
Electronic_ISBN :
1-4244-0140-2
DOI :
10.1109/NEMS.2006.334832
