Radiation heat flux of the open-cellular porous gas burner

摘要

Radiation heat flux from the combustion of the methane-air premixed gas on an open-cellular porous burnerwas investigated experimentally and numerically. In the experiment, an alumina-cordierite (Al-Co) havingpores per inch (PPI) of 20 and porosity (φ) of 0.875 was examined. Radiant output from the porous burnerwas measured based on a two-color radiometry. For the analysis, we assumed that the chemical kinetics ofgas-phase (Energy equation) reactions was governed by a single-step Arrhenius rate expression. To evaluatethe radiative transports in the solid-phase energy equation, the equation of transfer for the radiation field in aporous burner was solved using the P1 approximate method. The stable combustion of the present burnerwas characterized by flash-back limits, where the equivalence ratio (Φ) was around 0.48 to 0.5, and blow-offlimits (Φ was around 0.58 to 0.64). The radiant outputs depended on Φ and Reynolds number (Re).Predicted results of the dimensionless forward radiative heat flux (Ψ+) and the burner surface temperature(TS) were reasonably compared with experimental data. Reasonable agreement between theory andexperiment was obtained, and thereby the validity of the present theoretical model for predicting the radiationfrom a porous burner was confirmed.