In the present paper

the cold loss of a fridge when unloaded was studied through an experiment

and an improvement was proposed. First

the heat transfer process between the fridge interior and the external environment was simplified into a one-dimensional heat conduction process. On an all-weather simulation experiment platform

to investigate the effect of ambient temperature on cooling capacity loss

the ambient temperature was set to 5

10

15

20

25

30

35

and 40 ℃ with a fixed ambient humidity of 80%. To investigate the effect of ambient humidity on cooling capacity loss

the ambient humidity was set to 55

65

75

85

and 95% with a fixed ambient temperature of 25 ℃. The temperature of the inner and outer walls for every combination of the above two series of parameters was measured when the refrigerator was unloaded. According to the Fourier heat conduction law

the heat flux of each wall can be obtained

and then the cold loss is calculated. The results show that the cold loss of the refrigerator increases with ambient temperature

and the ambient humidity has no effect on cooling capacity loss. The cold loss of the refrigerator back wall is obviously greater than that of the other walls

while that of the top wall is smaller. The insulation of the refrigerator back wall is thickened to decrease the entire cold loss

and the insulation of the refrigerator top wall is made thinner to guarantee the refrigerator storage capacity. This leads to an approximately uniform cold loss distribution of the refrigerator walls.