Abstract: On the basis of the experimental data to verify the reliability of the numerical simulation results, the flow field and temperature field distribution characteristics in preheating stage of forced convection oven with different fan positions were compared and studied. The results show that, the flow field distribution of the fan rear mounted convection oven presents the characteristics of symmetry about the fan axis. Under the extrusion of the suction air flow of the fan, the outlet air flow will first arrive near the wall of the cavity, which makes the wall surface prone to appear high temperature region corresponding to the eddy current scale. In the flow field of the fan top mounted convection oven, it is easy to form large-scale airflow vortex in the middle of the fan. The outlet air flows around the central vortex, and the temperature field is low in the middle and high around. And the vertical plane temperature difference of the fan rear mounted convection oven is smaller, while the horizontal plane temperature difference of the fan top mounted convection oven is smaller. The results provide a useful reference for the selection of fan position and the improvement of temperature field uniformity of convection oven.

Key words: Forced convection oven, Flow field characteristics, Temperature field characteristics