▎ 摘　　要

Addition of graphene nanoplatelet (GNP) into water is a promising method for improving cold storage system performance, and its application requires comprehensive understanding of solidification behavior of GNP-water nanofluid. In the present study, the influences of GNP mass concentration, cold storage cavity size and shape on solid-liquid interface evolution, temperature distribution, streamline profile as well as solidification rate are numerically analyzed. The enthalpy-porosity technique is adopted to track solid-liquid interface. The results show that the enhancement effect of GNPs on solidification is mainly reflected in the final stage in which heat conduction is predominant; the solidification occurs at the bottom of cavity in the early stage, and the solid-liquid interface is similar to the shape of cavity itself and then tends to be circular in the middle and final stages respectively; the reduction degree of solidification time reaches 30.1% at GNP mass concentration of 1.2 wt% under present simulation conditions; decreasing cavity size and adopting triangular cavity are beneficial for promoting the solidification, but they will suppress the enhancement effect of GNPs on solidification.