AUTHOR=Ji Leilei , Agarwal Ramesh K. , Kan Kan , Tao Ran , Yang Yang , Presas Alexandre TITLE=Editorial: Optimal design and efficiency improvement of fluid machinery and systems JOURNAL=Frontiers in Energy Research VOLUME=11 YEAR=2023 URL=https://www.frontiersin.org/journals/energy-research/articles/10.3389/fenrg.2023.1238721 DOI=10.3389/fenrg.2023.1238721 ISSN=2296-598X