Experimental and numerical investigation of heat transfer modes on pot surfaces in a power range of a cooking porous burner

• Published in: Journal of cleaner production 2024-11, Vol.478, p.143952, Article 143952
• Main Authors: Soltanian, Hossein, Targhi, Mohammad Zabetian, Ashouri, Ali, Maerefat, Mehdi
• Format: Article
• Language: English
• Subjects: CO emission; Domestic porous burner; Heat transfer; Natural gas; Radiation and convection
• ISSN: 0959-6526
• DOI: 10.1016/j.jclepro.2024.143952

The investigation of convective and radiative heat transfers to a cooking pot in a porous burner, coupled with an analysis of the pot's bottom and side contributions to total heat transfer, remains an underexplored area of research. In this study, we adopt a comprehensive approach, combining experimental measurements and 3D numerical models, to explore the practical application of a Silicon carbide porous burner fueled with natural gas in cooking pots with power ranging from 12.15 kW to 31.04 kW. Three primary aspects are examined: differentiating between radiative and convective heat transfer contributions, investigating porous mixing characteristics, and analyzing the burner's thermal and combustion efficiencies. To facilitate this investigation, a dedicated test bench is meticulously designed and constructed, equipped with state-of-the-art measuring instruments to effectively monitor the thermal behavior of the heating process. The results reveal that the higher Damköhler number at higher power, driven by the dominance of chemical time over mixing time, accentuates the importance of chemical reactions in heat transfer to the pot. Moreover, increasing the power leads to a reduction in the burner's overall thermal efficiency, from 29.2% to 18.8%, due to a higher energy waste percentage, escalating from 45.12% at P = 12.15 kW to 65.31% at P = 31.04 kW. This increase in power also strengthens the downward movement of the flame and its detachment from the pot surface. The pot's bottom contribution to total heat transfer ranged from 76.7% to 95.5%, with convection alone accounting for over 98% in all cases. Consequently, optimizing the pot bottom geometry for the purpose of enhancing convection presents promising avenues for significantly boosting thermal efficiency. These findings highlight the potential of the investigated porous burner for efficient and clean combustion in cooking appliances. [Display omitted] •Pot bottom's significance surpasses pot side in heat transfer, contributing 76.7%–95.5% of total rate.•The Convection contribution surpasses 98% with respect to the total heat transfer across all powers.•At 12 kW, the heat transfer rate is 3.37 kW, rising to 6.35 kW at 30 kW.•Thermal efficiency drops from 29.2% to 18.8% by increasing power from 12 to 30 kW.•CO emission is kept under 10 ppm, meeting acceptable limits for domestic use.