We consider the grid resolution necessary to resolve combustion in a mixture of calorically imperfect ideal gases described by detailed kinetics and multicomponent transport.Using the steady premixed laminar flame as ...We consider the grid resolution necessary to resolve combustion in a mixture of calorically imperfect ideal gases described by detailed kinetics and multicomponent transport.Using the steady premixed laminar flame as a paradigm,the required spatial discretization to capture all detailed physics in the reaction zone is found via 1)determination of the finest grid used in a standard software tool which employs adaptive mesh refinement,2)examination of peak values of intermediate species mass fractions in the flame zone as a function of grid size,3)a formal grid resolution study,and 4)a robust new eigenvalue analysis developed to estimate the finest length scale.Application to laminar premixed flames in hydrogen-air flames reveals that the finest length scale is on the order of 10^(−4) cm for combustion at atmospheric pressure.Resolution at this scale is shown to be necessary to capture detailed species mass fraction profiles;other features such as steady flame speeds and equilibrium thermochemical properties do not have such a stringent length scale requirement.展开更多
基金support of the Chemistry Division of Argonne National Laboratory,the Center for Applied Mathematics at University of Notre Dame,and the National Science Foundation under grant CBET-0650843.
文摘We consider the grid resolution necessary to resolve combustion in a mixture of calorically imperfect ideal gases described by detailed kinetics and multicomponent transport.Using the steady premixed laminar flame as a paradigm,the required spatial discretization to capture all detailed physics in the reaction zone is found via 1)determination of the finest grid used in a standard software tool which employs adaptive mesh refinement,2)examination of peak values of intermediate species mass fractions in the flame zone as a function of grid size,3)a formal grid resolution study,and 4)a robust new eigenvalue analysis developed to estimate the finest length scale.Application to laminar premixed flames in hydrogen-air flames reveals that the finest length scale is on the order of 10^(−4) cm for combustion at atmospheric pressure.Resolution at this scale is shown to be necessary to capture detailed species mass fraction profiles;other features such as steady flame speeds and equilibrium thermochemical properties do not have such a stringent length scale requirement.
