Feasibility and adaptability investigation on wet hydrogen dehumidification using vortex tube

Abstract

This paper aims at exploring the feasibility of removing water vapour from wet hydrogen by vortex tube. For this purpose, a numerical model is developed for wet hydrogen condensing flow by adding two transport equations. Three different operating parameters, cold mass fraction, inlet pressure and molar fraction of water vapour, are discussed in terms of the impact on the flow and condensation process. The results show that the increase of the inlet pressure and the cold mass fraction can provide a favourable condensation environment for water vapour, which resulting in the increase of the number of droplets and mass fraction of the liquid. Condensation process is aggravated with high molar fraction of water vapour at inlet, although there is no significant change in pressure and temperature fields. Furthermore, a comprehensive study is performed by analysing the dehumidification performance and entropy generation. The maximum value of dehumidification performance up to 83.12% while cold mass fraction is 0.8218 and inlet pressure is 5 bar, which shows a good feasibility for wet hydrogen dehumidification.