Using a wide field stereo-microscope,a high-speed camera and a CCD video camera,liquid dryout behaviors and axial wetting height in vertical rectangular capillary microgrooves were observed and measured under the conditions of pure evaporation and boiling heat transfer.

Based on the fundamental mass conservation equation and considering the special characteristics of fluid flow and heat transfer in bilaterally heated annuli, a physical model used to predict dryout in bilaterally heated annuli is proposed.

Based on the theory of fluid flow and heat transfer in porous media with inner heat source, the phenomenon of membrane dryout in DMFC is studied quantitatively.

the electrolyte in the battery nearly dry-out,the use of PE separators,charging process and the temperature rising as well.

Based on an analysis of the two-phase flow pattern and the dry-out phenomenon, it was clear that annular flow was the predominant flow pattern, and liquid entrainment and deposition were the most important mechanism to sustain the annular flow during the heat absorbing boiling process of CO_2.