DSMC simulation of two-step dissociation-recombination of hydrogen on tantalum surface

Abstract

The presented work is devoted to the development of new approaches to simulating heterogeneous reactions of hydrogen dissociation and recombination during its interaction with the solid surface within the framework of the direct simulation Monte Carlo (DSMC) method. The DSMC algorithm including a two-step model of hydrogen dissociation is developed. A new technique for simulating heterogeneous reactions within the framework of the DSMC method is proposed, in which the reaction rate constant depends on the gas and surface temperature. The algorithm is verified on the example of a heated infinite tantalum wire placed in a hydrogen atmosphere. The influence of different approaches to simulating heterogeneous reactions on the flux of atomic hydrogen is studied. The results are compared with the results of simulation within the framework of the continuum approach. The developed approaches expand the possibilities of the DSMC method for the study of gas flows taking into account the influence of heterogeneous reactions.