A bibliometric analysis of Stirling engine and in-depth review of its application for energy supply systems

With the great advantages and continuous innovations, prolific research efforts have been devoted to the Stirling engine (SE) domain driven by the sustainability development. In this study, a bibliometric analysis is conducted to explore the research tend and hotspots of SE. The country co-authorship, institute co-authorship and keyword networks are engendered from the visual map using VOSviewer, showing China ranks the first with the total number of published articles and the majority publications are presented by Chinese Academy of Sciences. Owing to the highest node centrality, the research findings in USA can be considered the most influential and greatly worthy being referred, particularly represented by the early contribution for thermo-acoustic SE. The total 7 keyword clusters are classified through the top terms in Citespace and 4 of them are related to its energy supply system, demonstrating the typical application of SE-based combined heat and power (CHP) and integrated multi-energy complementary system have gained much attention. Based on this, a detailed review of SE-based energy supply systems is further conducted through the system forms, 4E performance evaluation and soft model combing optimization solutions. Several relevant issues hindering the improvement of these terms are summarized, providing the potential guides to help develop the SE-based energy supply system.