Experimental study on the airflow dynamics and particulate matter emission characteristics of cooking fumes during frying, roasting, and deep-frying

Abstract

Clarifying the characteristics of thermal plume airflow dynamics and particle characteristics during different cooking processes is helpful for efficiently controlling cooking fumes. In this study, the flow and emission characteristics of cooking fumes produced during frying, roasting, and deep frying were investigated using quantitative schlieren techniques and particulate matter sensors. The results show that frying, roasting, and deep-frying have smaller vortex areas, but different to that produced when simply heating edible oil, with the three cooking scenarios exhibiting plume dispersion angles that are, on average, approximately 20° larger than that observed for the heated-oil case. Furthermore, the emission velocity of the source ranged from 0 to 0.5 m/s for the four cases (within a distance one-times the diameter of the emission source). The velocity of the heated-oil case was generally Gaussian distributed, whereas those of the cooking cases were parabolically distributed. All cases exhibited linear variations in sectional diffusion diameter and flow rate along the vertical direction. The three cooking cases exhibited linearly fitted slopes that are approximately 1.0–2.0-times greater than that of the heated-oil case, which is reflective of more ambient air entrained during cooking. Particles 1–2.5 μm in size were observed for the three cooking cases, while the deep-frying case exhibited an average particulate mass concentration more than twice that observed for the heated-oil, which significantly increases the danger of exposure to oil-fume particles. In summary, detailed cooking-fume data serve as boundary conditions for simulations and provide crucial insight for effectively capturing cooking fumes.