Design and development of natural-draft Ethanol/LPG burner for heavy-duty cooking

A natural-draft, heavy-duty cooking burner was designed and developed as a fuel-flexible burner capable of burning both liquefied petroleum gas (LPG) and Ethanol. The burner has great potential to replace LPG with ethanol to reduce the consumption of fossil fuels. Ethanol is a renewable fuel; it can be produced domestically from agricultural products. However, its heating value is lower than that of LPG. Thanks to the advantage of combustion in a porous medium to create heat recirculation, the flame temperature is higher than that of the free flame. Using a column embedded in the burner wall, liquid ethanol is vaporized without external heating and atomization. A critical criterion for the burner is to stabilize the flame inside the porous medium so that flow velocity equals burning velocity. A common gas injector can be used to switch between LPG and ethanol while maintaining better combustion and thermal performance compared to a conventional LPG burner and previous ethanol burners. The proposed burner has a compact combustion chamber, but it yields a higher combustion temperature because it stabilizes the flame at greater amounts of primary air with a high turn-down ratio.