Thermal energy, process, and transport intensification - a brief review of literature in 2021 and prospects

This review provides a brief literature survey recorded by the Web of Science (WoS) in 2021 on the studies of heat transfer enhancement (HTE), thermal energy, process, and transport intensification technologies. A topic search containing “heat transfer” or “heat transport” or “thermal transport” in the WoS resulted in over 31, 360 papers published in 2021 and more than 30% were relevant to HTE, thermal energy, process, and transport intensification, which indicates the importance and rapid development of these technologies and their applications. The chosen studies focus on HTE, thermal energy, process, and transport intensification, which are grouped into heat conduction enhancement, convection HTE, boiling and condensation HTE, radiation HTE, thermal energy and process intensification, and cross disciplinary research involving two or more techniques. Heat conduction enhancement research covers the research topics on thermal conductivity augmentation using various methods for thermal interface materials, phase change materials (PCMs), composite materials with nano-additives, nanocoatings, nanofluids, finned metal foam, and fins in heat exchangers. Convection HTE research includes passive, active, and compound techniques and their engineering applications. Boiling and condensation HTE research is critical in the development of advanced and cutting-edge thermal energy and process intensification technologies. Radiation HTE research focuses on near-field radiation and thermophotovoltaic cells. Thermal energy and process intensification research involves thermal and power systems, energy conversion, energy storage, thermal processes, renewable energy, and thermal management of electronics and high-end equipment, and cross disciplinary topics. The prospects of thermal energy, process, and transport intensification technologies are given according to this literature review. Studies of thermal energy, process, and transport intensification techniques are immense, encompassing every aspect from understanding the experimental results, observed phenomena, fundamental theory, and physical mechanisms of various intensification techniques to their practical engineering applications. Engineering design, experimental and numerical studies of emerging intensification techniques using new interfacial materials, nanofluids, micro- and nanostructures and microchannels, combination of two or more methods, etc. have been conducted. Compound enhancement techniques incorporating conventional and innovative techniques and their applications in energy recovery, energy conversion, energy storage, renewable energy, combined heat, cooling and power generation technologies, hydrogen production and energy system, thermal management, etc. play a crucial role in achieving zero carbon target by 2050 and provide opportunities for research and development of innovative intensification technologies.