Computational Fluid Dynamics (CFD) Technology Methodology and Analysis of Waste Heat Recovery from High-Temperature Solid Granule: A Review

High-temperature solid granules are by-products produced by various industrial processes and contain an obvious quantity of waste heat. Therefore, recovering their heat can not only reduce energy costs but also prevent polluting the environment, which has a significantly valuable sense of sustainable development. Computational fluid dynamics (CFD) technology is widely used to solve challenges involving heat recovery, which can simulate the heat and mass transfer processes of the gas–solid two-phase flow. Herein, a review about the mass flow analysis methods, including the Euler–Euler and Euler–Lagrange methods, as well as heat transfer mechanisms, covering heat conduction, heat convection and heat radiation, is made. Meanwhile, the bases of numerical models, mass flow and heat transfer are also summarized. In addition, at the end of the paper, a prospect about this research field is proposed. This article not only reviews common research methods but also summarizes relevant new models and methods that have emerged in recent years. Based on existing work, it both fully demonstrates the widespread application of CFD technology in the field of recovering heat from high-temperature solid granule fields and summarizes the development trends and further utilization prospects of the technology.