An updated review on working fluids, operation mechanisms, and applications of pulsating heat pipes. (July 2021)

• Record Type: Journal Article
• Authors: Xu, Yanyan; Xue, Yanqin; Qi, Hong; Cai, Weihua
• Is Part Of: Renewable & sustainable energy reviews. Volume 144(2021)
• Publication Date: 2021-07
• Subjects: Pulsating heat pipe -- Nanofluids -- Operation mechanism -- Flow regime -- Solar collector; Renewable energy sources -- Periodicals; Power resources -- Periodicals; Énergies renouvelables -- Périodiques; Ressources énergétiques -- Périodiques; 333.794
• DOI: 10.1016/j.rser.2021.110995
• Languages: English
• ISSNs: 1364-0321

Abstract

Abstract: Global demands for sustainable energy are rising rapidly due to the ever-increasing energy crisis. Efficient energy management is one of the feasible methods to solve the existing energy crisis, and has attracted extensive attention. Pulsating heat pipe (PHP), as a potential thermal management system, has broad application prospects due to its simple structure, low cost and excellent heat transfer performance. Numerous researchers are not only committed to enhance heat transfer performances of PHPs from the aspects of working fluids, but also to further understand the operation mechanisms. The purpose of this review is to summarize and discuss the research status and development trends of working fluids, operation mechanisms, and applications of PHPs in recent years. This review highlights the latest research progress in the area of nanofluids and the recent advances in applications of nanofluids in PHPs, including the preparation and stability improvement methods of nanofluids, thermophysical and rheological behaviors of nanofluids, mechanisms responsible for thermal conductivity enhancement in nanofluids, and heat transfer mechanisms in PHPs with nanofluids. In addition, operation mechanisms of PHPs are discussed from the aspects of theoretical models of PHPs and flow regimes in PHPs. Moreover, recent advances in applications of PHPs in electronic cooling, solar collectors, waste heat recovery and machining process are presented. Subsequently, the optical properties and photothermal conversion performances of nanofluids are also introduced in details. Finally, the existing challenges and suggested directions on PHPs with nanofluids are discussed. Highlights: Latest research progress in the area of nanofluids and the applications of nanofluids in PHPs are introduced. Possible heat transfer mechanisms in PHPs with nanofluids as working fluids are reviewed. Operation mechanisms are discussed from the aspects of theoretical models of PHPs and flow regimes in PHPs. Potential applications, challenges and future research directions of PHPs are presented.