Effect of pressure on the hydrogen dissociation degree in a hot tube

The effect of pressure decrease on the degree of dissociation of hydrogen flowing inside a hot tube was studied. The experimental data were analysed using the previously developed thermal model of the reactor. The heat exchange of gas with the tube wall was estimated based on the direct Monte Carlo simulation. It was shown that decreasing the pressure from 20 mm Hg down to 1 mm Hg leads to a slight increase in the degree of hydrogen dissociation, from 11% up to 13%.