Numerical Simulation of Rapid Cold Release Characteristics of Plate-Fin Phase Change Cold Storage Unit

The paraffin phase change cold storage technology has the advantages of high cold storage density, but the low thermal conductivity of paraffin limits its application in the field of rapid cold release. Therefore, this paper designs a plate-fin cold storage device using aluminum alloy material and establishes a two-dimensional numerical simulation model to investigate the output characteristics of the cold storage device under conditions of inlet flow rate, temperature, fin spacing, initial temperature, and external constant power heating. The results indicate that the designed plate-fin cold storage device can release all its cold capacity within 260 s. To increase the cold storage density, the optimal fin height is 10mm, and the fin pitch is in the range of 3-4 mm. Increasing the flow rate and inlet temperature can significantly enhance the cold release power. It is observed that the initial temperature has almost no effect on the melting rate of paraffin. When the difference between the initial temperature and the phase change temperature is small $\left(1-3^{\circ} \mathrm{C}\right)$, the instantaneous cold release power does not change significantly. The cold storage device can achieve constant power cold release, and as the cold release power increases, the outlet temperature rises more rapidly.