Hydrogen detectors
VARIATIONAL MODEL FOR MULTICOMPONENT ADSORPTION OF HYDROGEN-WATER MIXTURES BY THE SENSOR SURFACE
M. M. Penkov, N. V. Dolgorukov, I. V. Naumchik
Mozhaisky Military Space Academy 13 Zhdanovskaya nab., St. Petersburg, 197082, Russia Phone: (812) 235-85-55
The variational statement of the joint hydrogen and water sorption dynamics problem has been justified allowing the use of simplified calculation procedures for the processes of hydrogen interaction with surfaces.
A peculiar feature of the proposed model of a sensor as a continuum is the representation of any differential volume in the form of a two-phase system. Mass transfer due to sorption processes is taking place between the gaseous and solid phases. The temperature within the differential volume is considered identical for both phases. The adsorbent-adsorbate (solid phase) sorption system has been described by parameters characterising it on the whole, i. e. without account of the real structure of the adsorption phase. Such an approach allows the use of sorption-desorption characteristics to be deter-
mined experimentally and obtain a mathematical model being suitable for the description of heat and mass transfer processes both with the availability of gas adsorption in the surface layer and in material micropores.
In order to obtain the variational statement of the mathematical model for the processes of molecular heat and mass transfer, we have used the basic variational principle of classical phenomenological thermodynamics, namely, the V. V. Chikovani's principle.
The variational description of heat and mass transfer processes in a continuum taking into account internal sorption processes allows one to reduce the order of the derivative with the coordinate and use approximate analytical methods for solving problems (Ritz method) or use finite-element approaches.
ISJAEE Special issue (2003)