On September 14, the "2nd Symposium on Fluid Interface Instability and Multiphase Turbulence" successfully concluded in Hefei. This symposium brought together experts and scholars from dozens of research institutions and universities, including the China Academy of Engineering Physics, the Chinese Academy of Sciences, Peking University, Shanghai Jiao Tong University, and Beijing Institute of Technology. They conducted in-depth discussions on cutting-edge topics such as interface instability, shock wave-driven multiphase flow and mixing, and interactions between multiphase flow and complex media. As a key tool in experimental fluid mechanics research, Particle Image Velocimetry (PIV) instruments have demonstrated unique differentiated value in multiple research directions:
Interface instability is widely present in multiphase fluid systems. Its nonlinear evolution, mode coupling, and turbulence transition processes are current research hotspots, such as the cross-scale evolution from linear growth to turbulent mixing, including vortex structure generation, breakdown, merging, and statistical laws of mixing layers.
The Tomographic PIV developed by HF Agile Device Co.,Ltd consists of 4 Revealer high-speed cameras. It can realize full-field measurement of three-dimensional velocity vectors in turbulent fields, extract key features such as vortex structure evolution and shear layer instability, and provide experimental data for the statistical modeling of multiphase turbulence.
Fluid interface instability driven by shock waves is an important research direction in high energy density physics. Interface instability under shock wave action is usually accompanied by complex multi-physical coupling phenomena, which puts extremely high demands on diagnostic technologies.
The self-developed Revealer PIV instrument by HF Agile Device Co.,Ltd can accurately measure the velocity field distribution in regions where typical structures such as shock waves, shear layers, separated flows, and transition exist. It obtains detailed 2D and 3D velocity vector diagrams, providing data support for studying the propagation characteristics of shock waves, energy transfer during transition, and the generation and development of vortex structures.
In typical scenarios such as spray combustion and microfluidics, there widely exist complex flows with coexisting multiphase media such as gas-liquid, gas-solid, and liquid-liquid, involving strongly coupled phenomena of multiple processes including interface deformation, droplet breakup, and instantaneous slip. Liquid-liquid and liquid-solid collision processes are usually accompanied by complex vortex generation, interface mixing, and vorticity transport.
The Revealer PIV instrument of HF Agile Device Co.,Ltd can observe the formation, development, and breakdown processes of vortices, and measure the velocity fields and vorticity fields inside them.
As the "eyes" of experimental fluid mechanics research, Particle Image Velocimetry (PIV) technology continues to play a core observation role in fields such as interface instability, turbulent mixing, and multiphase flow. This symposium not only showcased the cutting-edge progress of China in the research of fluid interface and turbulence but also highlighted the supporting value of advanced measurement technologies for breakthroughs in basic science. As PIV technology develops towards higher spatiotemporal resolution and synchronous measurement of multiple physical fields, it will play a key role in major national applications such as aerospace flight, energy fusion, and environmental engineering.
