应土木工程学院陈文礼教授和陈冠斌副研究员的邀请，韩国釜山国立大学（Pusan National University），韩国翰林院院士、Journal of Visualization主编Kyung Chun Kim教授将于2026年10月10日到10月24问我校，并作报告，欢迎感兴趣的师生参加。
报告时间：2026年10月14日 9:30-11:00
报告地点：土木工程学院303会议室
报告主题：Turbulent flow and bubble characteristics of bubbly plunging jet
Abstract
Turbulent plunging jets are widely observed in natural and engineering systems. When a plunging water jet impinges on a free surface, ambient air can be entrained and a bubbly jet is formed in the receiving pool. This study experimentally examines the three-dimensional liquid phase velocity field and bubble statistics of the turbulent plunging water jet with air entrainment over three Froude-number conditions. Measurements were performed using time-resolved three-dimensional Lagrangian Particle Tracking (3D-LPT) method with alternating illumination system. The liquid velocity field was reconstructed using the Shake-The-Box algorithm and Vortex-In-Cell sharp reconstruction, while bubble motions and size statistics were obtained from image processing. The bubbly jet exhibits flow characteristics that differ from those of a plunging jet without air entrainment. Pinch-off of the entrained air cavity generates near-surface ring-like vortical structures, which are stretched and tilted into cane-shaped structures by the descending bubbly jet. The bubbly jet does not exhibit a classical constant-velocity potential core; instead, bubble clusters produce a near field acceleration of the centerline velocity and intermittent high-speed liquid motions. The bubble-size distribution and void fraction are strongly dependent on Froude number as well as Reynolds number conditions. We found new power-laws in the bubble size spectra independent on Froude number. Entrained bubbles enhance liquid entrainment, promote radial redistribution of axial momentum and amplify the axial velocity fluctuations. After normalization by proper velocity and length scales, the first- and second-order moments in liquid phase statistics exhibit self-similarity although their amplitudes remain dependent on the bubble population.
报告人Kyung Chun Kim教授简介
Prof. KC Kim received his MS and Ph.D degree at KAIST, Korea in 1981 and 1987, respectively. Since 1983, he is a professor at School of Mechanical Engineering in Pusan National University (PNU), Korea. He was invited as a visiting professor from Ottawa University in Canada for 1989-1990. He was joined in University of Illinois, Urbana-Champaign, USA as an invited professor for 1996-1997. He was invited as a special foreign professor from the University of Tokyo, Japan for 2009-2010. On the basis of his research outcomes, he became a member of National Academy of Engineering in Korea in 2004. He received Nakayama award in 2012, Asanuma award in 2014 and Leonardo da Vinci award in 2025. KC Kim was selected as a PNU Distinguished Professor in 2018. He is currently serving as an Editor in Chief for Journal of Visualization. In 2020, he was selected as the director of Regional Leading Research Center for Eco-friendly Smart Ship. He is top 1.2 percent scholar in his research field (Stanford University) and has published 343 SCIE international journal papers, which have been cited more than 12089 times and an H-index factor of 233. His research interests include: Microfluidics, Turbulence, Two-Phase Flows, Flow Visualization, and Artificial Intelligence.
