Flow direction-dependent elastic instability in a symmetry-breaking microchannel

• Main Authors: Zhang, Wu, Wang, Zihuang, Zhang, Meng, Lin, Jiahan, Chen, Weiqian, Hu, Yuhong, Li, Shuzhou
• Other Authors: School of Materials Science and Engineering
• Format: Article
• Language: English
• Published: 2022
• Subjects: Engineering::Materials; Viscoelastic Fluid; Elastic Instability
• Online Access: https://hdl.handle.net/10356/160792
• Institution: Nanyang Technological University

This paper reports flow direction-dependent elastic instability in a symmetry-breaking microchannel. The microchannel consisted of a square chamber and a nozzle structure. A viscoelastic polyacrylamide solution was used for the instability demonstration. The instability was realized as the viscoelastic flow became asymmetric and unsteady in the microchannel when the flow exceeded a critical Weissenberg number. The critical Weissenberg number was found to be different for the forward-directed flow and the backward-directed flow in the microchannel.