Air volume improvement in the duct system in frost-free refrigerators based on the CFD method

The air volume of the duct system is important to the performance of the frost-free refrigerator. This paper is focused on the air volume improvement based on the optimization of the duct structure. Firstly, the computational fluid dynamics model of the air duct system in frost-free refrigerator is established, and the grid-independent and validity of the model is investigated according to the experimental data. Secondly, the distribution of velocity, pressure and vortex in fan duct system is studied with the operating conditions, and also the factors of the flow efficiency in duct system are analyzed. Finally, a new air duct system structure is proposed based on the multi-outlet volute and the method of tongue isolation. The results show that the outlet pressure, air volume and air velocity in the new air duct are obviously improved, which means that the new air duct system has a better air supply capability, and it also indicates that the refrigerator has a better cooling effect.