Radiation Heat Flux of the Gas Burner using Open-cellular Porous Media

Abstract

Abstract

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Radiation heat flux from the combustion of the methane-air premixed gas on???????????????????????????????????????? an open-cellular porous burner was investigated experimentally and numerically. In the experiment, an alumina-cordierite (Al-Co) having pores per inch (PPI) of 13 and porosity (f) of 0.872 was examined. Radiant output from the porous burner was measured based on a two-color radiometry. For the analysis, we assumed that the chemical kinetics of gas-phase (energy equation) reactions was governed by a single-step Arrhenius rate expression. To evaluate the radiative transports in the solid-phase energy equation, the equation of transfer for the radiation field in a porous burner was solved using the P₁ approximate method. The stable combustion of the present burner was characterized by flash-back limits, where the equivalence ratio (F) was around 0.48 to 0.5, and blow-off limits???????????? (F was around 0.62 to 0.76). The radiant outputs depended on F and Reynolds number (Re). Predicted results of the dimensionless forward radiative heat flux (Y⁺) and the burner surface temperature (T_S) were reasonably compared with experimental data. Satisfactory agreement between theory and experiment was obtained, and thereby the validity of the present theoretical model for predicting the radiation from a porous burner was confirmed.

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Keywords: Radiation heat flux, Porous burner, Premixed gas, Open-cellular porous material