Dimethyl carbonate (DMC) is widely used in organic synthesis and lithium battery industries. Melt crystallization, as a green manufacturing method, is highly important for the production of DMC with ultra-high purity. Herein, a two-dimensional transient Computational Fluid Dynamics (CFD) model was developed utilizing the enthalpy-porosity approach to simulate the layer melt crystallization process of DMC. The fluid dynamic and thermodynamic phenomena during the evolution of the crystal layer under various conditions were investigated. The findings suggest that natural convection heat transfer plays a crucial role in determining the distribution of the crystal layer. Moreover, the heating temperatures were optimized based on the specificity of DMC melt layer crystallization to enhance the heat transfer during crystallization. Afterwards, a general correlation model for crystallization time, crystal fraction, and heat transfer rate was established by non-dimensional analysis. The results presented in this work could be used to optimize the melt crystallization process of DMC and to facilitate better understanding of heat and mass transfer during melt crystallization.