Numerical Simulation Of Methane Filtration Combustion In Porous Media For Hydrogen Production

Recently, with the rapid growing of China's economy, the problem of the energy crisis and irrational structure of energy restricts the sustainable development of economy. To solve the problem, the development of new energy sources and making full use of existing energy sources are of great importance. Superadiabatic combustion of gaseous and liquid fuel in porous media is an advanced technique for energy utilization. Since hydrogen is a very promising energy for the future, methane filtration combustion in porous media for hydrogen production draws more and more attentions from the combustion community and industry.In this paper, a numerical research is carried out on the superadiabatic combustion of methane in porous media for hydrogen production. A one-dimensional two-temperature model based on the local thermal non-equilibrium is presented. Temperature and species distributions in the combustion chamber are calculated. The influences of major parameters on the combustion and methane to hydrogen conversion characteristics are discussed based on the numerical results.From the numerical simulation the following conclusions are drawn:1 In steady-state filtration combustion, in the preheat zone, the temperature of solid is higher than that of gas mixture, while in the downstream of combustion zone, the temperature of gas is higher than porous media, so the heat flux is from gas to solid.2 In steady-state filtration combustion, the peak temperatures of gas and porous media are influenced strongly by the fuel-air equivalence ratio. Under the ultra-rich condition, the peak gas temperature of decreases while the mole fraction of H2 and CO increase with increasing equivalence ratio and. In consideration of the hydrogen production, the conversion of methane to hydrogen also increases with increasing equivalence ratio, but not obviously. The result of numerical simulation in this paper is compared with the experimental data of Lawrence et al, and a reasonable agreement is observed.3 The temperature and the species concentrations in the hydrogen production by methane reformation in a porous media combustor also depend on themal properties as well as the construction and geometry parameters of the porous media (thermo-conductivity, heat loss coefficient, porosity,etc.).