This study investigates the characteristics of the flow field, temperature and concentration distributions produced during the cooking activity using a cooktop with two electric heaters under a wall-mounted range hood. Different range hood geometries under the different force conditions are investigated in this study. The computational fluid dynamics (CFD) software, ANSYS FLUENT, is adopted to validate the experimental data obtained from the real-scale laboratory model. The tracer gas of SF6 is used to represent the oil mist produced during the cooking process. The Reynolds-Averaged Navier-Stokes (RANS) approach with the realizable k-epsilon model is implemented in the numerical simulation. Two range hood geometries of the complete range hood and the simplified range hood are modeled into the simulation domain. The hybrid meshing is applied to the complete range hood domain and the structured meshing is applied to the simplified range hood. Three simulation cases have been tested, and those cases respectively consider the pure buoyancy force, the pure suction force, and the combined force. The pure buoyancy force cases consider two electric heaters with a fixed surface temperature of 360C and those with the combined power of 10,000 Watt. The case with the combined power of 10,000 Watt generates a vertical flow with a higher velocity, approximately seven times faster than that produced by the case considering the electric heaters with the fixed surface temperature of 360C. The pure suction force case considers two operating fans in the range hood, providing the combined exhaust flow rate of 12 m3/min. This case shows that a complete range hood can exert the suction force more effectively on the area below the hood than the simplified range hood. The cases of the combined force consider the simultaneous operation of both the electric heaters and the range hood fans. The suction force is dominant when the electric heaters have the surface temperature of 360C, and the range hood fans provide the exhaust flow rate of 12 m3/min. The suction force is equal to the buoyancy force on the monitoring point plan located in the middle region between a single electric heater with the power of 5,000 Watt and a single range hood fan with the flow rate of 6 m3/min. The combined force case also shows that the complete range hood has less SF6 gas leakage than that given by the simplified range hood. The average air temperature under the complete range hood is slightly higher than that under the simplified range hood. Maintaining an enough distance from the cooktop during the cooking activity is required to reduce the exposure of the hot air temperature and the SF6 gas leakage.

This study investigates the characteristics of the flow field, temperature and concentration distributions produced during the cooking activity using a cooktop with two electric heaters under a wall-mounted range hood. Different range hood geometries under the different force conditions are investigated in this study. The computational fluid dynamics (CFD) software, ANSYS FLUENT, is adopted to validate the experimental data obtained from the real-scale laboratory model. The tracer gas of SF6 is used to represent the oil mist produced during the cooking process. The Reynolds-Averaged Navier-Stokes (RANS) approach with the realizable k-epsilon model is implemented in the numerical simulation. Two range hood geometries of the complete range hood and the simplified range hood are modeled into the simulation domain. The hybrid meshing is applied to the complete range hood domain and the structured meshing is applied to the simplified range hood. Three simulation cases have been tested, and those cases respectively consider the pure buoyancy force, the pure suction force, and the combined force. The pure buoyancy force cases consider two electric heaters with a fixed surface temperature of 360C and those with the combined power of 10,000 Watt. The case with the combined power of 10,000 Watt generates a vertical flow with a higher velocity, approximately seven times faster than that produced by the case considering the electric heaters with the fixed surface temperature of 360C. The pure suction force case considers two operating fans in the range hood, providing the combined exhaust flow rate of 12 m3/min. This case shows that a complete range hood can exert the suction force more effectively on the area below the hood than the simplified range hood. The cases of the combined force consider the simultaneous operation of both the electric heaters and the range hood fans. The suction force is dominant when the electric heaters have the surface temperature of 360C, and the range hood fans provide the exhaust flow rate of 12 m3/min. The suction force is equal to the buoyancy force on the monitoring point plan located in the middle region between a single electric heater with the power of 5,000 Watt and a single range hood fan with the flow rate of 6 m3/min. The combined force case also shows that the complete range hood has less SF6 gas leakage than that given by the simplified range hood. The average air temperature under the complete range hood is slightly higher than that under the simplified range hood. Maintaining an enough distance from the cooktop during the cooking activity is required to reduce the exposure of the hot air temperature and the SF6 gas leakage.

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