In the present study, a numerical study was performed on a recently introduced Porous Radiant Burner (PRB) with an internal combustion regime. Environmental and energy saving aspects of the PRB were studied. The equations governing the combustion problem were solved by considering the solution assumptions and using a structured grid. The process of solving equations continued until a high accuracy and low residuals. There was a good agreement between the simulation results and the experimental data. Thermal and prompt NO formation was simulated using the resulting temperature and velocity domains. It was observed that due to the high pore density of the porous foam, the flame could not pass through it, and the temperature of the combustion products decreases sharply after entering the porous foam. Besides, as the firing rate increased, the radiant efficiency decreased, while the NO formation rate increased. However, the slope of the NO formation rate’s curve decreases by growing the input power, because, by increasing the input power, the regions with the temperatures of above 1800 K will be limited to the internal zone and cannot grow as fast as the input power. Moreover, two different designs were compared for a specific input power of 4.5 kW, a PRB with the input power of 4.5 kW, design #1, and three parallel PRBs with the input powers of 1.5 kW, design #2. It was found that design #1 is better from an environmental point of view, while design #2 is better from an energy saving point of view. In fact, from the energy saving and environmental points of view, the two designs work against each other. If the environmental and energy saving aspects of the PRB are taught to be of equal importance, design #1 would be the better choice.

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