Research Progress in Composite-enhanced Flow Boiling Heat Transfer for Refrigerants

Improvements in heat transfer performance and efficiency through a single heat transfer enhancement technology are limited. Hence, composite-enhanced heat transfer technologies must be developed to improve resource utilization rates and reduce energy consumption and carbon emissions. Refrigerants exhibit physical properties that significantly affect the energy transport in refrigeration systems. Based on the development trend of refrigeration systems characterized by miniaturization, reduced weight, energy savings, and efficient heat transfer, refrigerant composite-enhanced heat transfer can effectively improve the energy efficiency of refrigeration systems, which has been widely studied in recent years. This work summarizes the latest research progress in composite-enhanced flow boiling heat transfer for refrigerants, focusing on nanoparticles, metal foam, external field (ultrasonic/magnetic field/electric field), and environmentally friendly refrigerant mixtures. It also highlights the prospects and existing problems in the application of multi-field synergy and nanoparticle-metal-foam-refrigerant composite-enhanced heat transfer as a future research direction. The review provides insights and references for establishing a new multi-element refrigerant composite-enhanced system.