To optimize the thermal performance of a medical refrigerator

a composite cold thermal energy storage plate was considered. A design scheme for a composite cold thermal energy storage plate in a medical refrigerator with a uniform and controllable temperature field was proposed. An experimental platform was developed. A medical refrigerator and the composite cold thermal energy storage plate were designed according to the principle of composite cold thermal energy storage. From the perspective of the equal mass scheme and the equal phase-change latent heat scheme

the inner-wall temperature change and cold thermal energy storage time of the phase-change materials (n-tetradecane

CaCl2?6H2O

and water) in the cold thermal energy storage plate were compared. It was found that an equal mass combination of 1.5 kg n-tetradecane in the inner layer and 1.5 kg CaCl2?6H2O in the outer layer of the cold thermal energy storage plate produced the best performance. Further

the cold thermal energy storage duration

average temperature

maximum inhomogeneous coefficient

and the cooling discharge rate of the cold thermal energy storage plate with the best performance at 2–8 ℃ were compared with different positions in the medical refrigerator (horizontally located on both sides

stacked on both sides

diagonally placed

and perimetrically placed). The results indicated that the composite cold thermal energy storage plate placed diagonally had the longest storage duration; the average temperature for the four placement positions was within 2–8 ℃. When the two sides were stacked

the maximum inhomogeneous coefficient was the lowest

and the cold discharge rate of the cold thermal energy storage plate was the highest. Considering temperature uniformity as the priority

the cold thermal energy storage effect of an equal-mass combination scheme stacked on both sides was preferred. The experimental results provide a reference for promoting the application of composite cold thermal energy storage plates for medical refrigerators in cold-chain transportation.