The ASME Journal of Fluids Engineering (JFE) and the ASME Fluids Engineering Division (FED) present a special issue of papers that were presented at the 2023 ASME-JSME-KSME Fluids Engineering Division Summer Meeting (AJKFluids 2023). The first FED joint meeting of the mechanical engineering societies between the United States, Japan, and Korea was in 2011. The 2023 FED conference marks the second year with Japan as the host country. The conference cochairs were Dr. Takeo Kajishima (Osaka University) and Dr. Genta Kawahara (Osaka University) representing JSME, Dr. Kamran Siddiqui (University of Western Ontario) and Dr. Marianne Francois (Los Alamos National Laboratory) representing ASME, and Dr. Han Seo Ko (Sungkyunkwan University) and Dr. Gwang Hoon Rhee (University of Seoul) representing KSME.

The AJKFluids 2023 conference was held in Osaka, Japan, from July 9–13, 2023, at the Osaka International Convention Center. The special issue dedicated to this conference includes 12 papers invited based on their conference presentations and extended abstracts. The collection of topics includes both experimental and numerical studies on multiphase flow, turbomachinery, turbulent fluid motion, and applications with additive manufacturing. I am grateful for the assistance of the FED executive committee members who helped review the extended abstracts and select the paper contributions. Special thanks to Professor Philipp Epple, Dr. Marianne Francois, and Professor Ning Zhang.

The Special Issue also presents the winners of the Flow Visualization competition, organized by Professor Philipp Epple. The 2023 winners in the video category were as follows:

  • First Place: “Direct Numerical Simulation on Millimeter-sized Air Bubbles in Turbulent Channel Flow”, S. Kim et al.

  • Second Place: “LES/Lagrangian-particle-simulation of a Supersonic Reactive Turbulent Planar Jet”, J. Xing, T. Watanabe, and K. Nagata

  • Third Place: “Passively enhanced vortex-induced vibration response of side-by-side cylinders in turbulent flow”, Y. H. Irawan, S. A. Raza, and M.-J. Chern

  • Honorable Mention: “A multi-GPU based real-time large-eddy simulation of urban wind in Seoul”, M. Yang et al.

  • Honorable Mention: “Boundary-Layer Agitator for Advanced Convective Mixing”, R. Pham and C.-L. Chen

  • Honorable Mention: “Morphological Features of a Splashing Drop extracted using Explainable AI”, J. Yee et al.

In closing, my sincerest gratitude is extended to our colleagues who served as reviewers, and of course the authors, whose contributions comprise the special issue. I would also like to acknowledge the JFE guest editors, Dr. Xiang Yang and Dr. Deify Law, who shared in the responsibilities to support the special issue. We are indebted to the JFE editorial assistant, Ms. Colette Montague, who helped ensure timely processing, and the support of the ASME staff, especially Ms. Beth Darchi, Ms. Erica Hodge, and Ms. Tamiko Fung.