Conjugate heat transfer analysis using a simplified household refrigerator model

•A simplified domestic refrigerator is modeled using a conjugate heat transfer method.•The effect of radiation and inner structure on heat transfer and flow field is examined.•Radiation plays an important role in determining the heat transfer rate and flow field.•Inner structure increases the vertical temperature gradient and decreases the temperature homogeneity.

Air circulation and heat transfer in a simplified household refrigerator model was numerically studied. Three refrigerator configurations were analyzed and compared to highlight the influence of inner structures. The results show that radiation enhances heat transfer between evaporator and inner walls, resulting in a higher temperature gradient across the insulation foams and a higher heat loss rate. Radiation also weakens the natural convection but increases the air circulation between shelves. A vertical temperature stratification is observed in the fresh food compartment for all configurations. The shelves and food strengthen air circulations between the shelves and inner walls, which increases vertical temperature gradient and decreases the temperature homogeneity in the compartment.