We explore the dynamics of cleaning thick layers of soft-solid materials from horizontal surfaces using a turbulent impinging jet. These materials, which behave like solids until a critical yield stress is exceeded, exhibit fascinating flow behavior when exposed to the jet. Initially, the jet carves out a cavity through the material, which grows, evolves, and occasionally bursts in a visually striking manner. Our real-time, non-intrusive measurements capture the influence of layer thickness (1, 2, 4, 8 cm) and yield stress (0, 4.3, 10.8 Pa) on the evolving cavity shape and the rate of cleaning. The experiments also highlight the role of air entrainment in the cleaning process, with bubble characteristics such as size distribution and velocity being affected by the layer yield stress. This study reveals how increasing yield stress and layer thickness significantly alter the flow and cleaning patterns, offering new insights into the interplay of turbulence, material properties, and air entrainment. For more details, please refer to:H. Hassanzadeh, D. I. Wilson, I. A. Frigaard, and S. M. Taghavi, 'Turbulent impingement jet cleaning of thick viscoplastic layers', Journal of Non-Newtonian Fluid Mechanics (2024): 105264.
This work is licensed under the Creative Commons Attribution-NonCommercial 4.0 International License. Any reuse must credit the author(s) and provide a link back to this page.