Minimum diameters for CH4 /H2 -air mixtures: implications for natural gas cooktop burners
Résumé
The minimum detonation diameter for methane (CH4) / hydrogen (H2)-air mixtures is numerically evaluated to assess detonation risks in cooktops designed to work with natural gas. A one-dimensional mathematical model that considers heat and friction losses for detonations propagating in pipes is used for that purpose. The initial conditions are selected to emulate the operation of a commercial cooktop working with different CH4 /H2 blends. Results show that for H2 content in the blend higher than 45 %, a conventional cooktop air-fuel mixer may pose a detonation hazard since the minimum detonation diameters predicted by the model are smaller than the diameter of the mixing tube (i.e., dmin < dmixer). Additionally, the individual effect of equivalence ratio, Φ, and hydrogen content, % H2 , in the fuel blend are evaluated separately. An increased risk of detonation is present for (i) CH4 /H2-air mixtures with Φ → 1, and (ii) higher % H2 content.
Domaines
Milieux fluides et réactifs
Origine : Fichiers produits par l'(les) auteur(s)