Abstract
It is proposed that the gas permeabilities should be adopted as the indices for evaluating the characteristics of power generation and reliability of solid oxide fuel cells in this paper.
The gas flow properties in the ceramic membranes could be expressed as viscous flow and the theoretical gas permeability coefficients can be expressed as the function of the square of porosity and are proportional to the inverse of the viscosity or kinematic viscosity.
The gas permeation in porous alumina tube wall was measured in the tempereture range room temperature to 600°C with use of various gases such as H2, He, CH4, N2 and Ar. The flow velocity of gas is expressed in the order H2>He>CH4>N2>Ar, and these tendency coincides with the order of gas viscosity.
The gas permeability coefficients are preferable to analize the data and are expressed as the function of viscosity or kinematic viscosity of gases at high tempereture range.
