Approximation of the boundary-value problem of hydrogen thermal desorption by ODE system: convergence acceleration

Abstract

One of the technological challenges for hydrogen materials science (including ITER project) is the currently active search for structural materials with various potential applications that will have predetermined limits of hydrogen permeability. One of~the experimental methods is thermodesorption spectrometry (TDS). A hydrogen-saturated sample is degassed under vacuum and monotone heating. The desorption flux is measured by mass spectrometer to determine the character of interactions of~hydrogen isotopes with the solid. We are interested in such transfer parameters as the coefficients of diffusion, dissolution, desorption. The paper presents a distributed boundary value problem of thermal desorption and a numerical method for TDS-spectrum simulation, where only integration of a non-linear system of low order ordinary differential equations (ODE) is required. The method of convergence acceleration based on the allocation of integrable weak singularity is explained. This work is supported by the Russian Foundation for Basic Research (project 15-01-00744).