Free convection of yield stress fluids: The path between theory and observations
Time: Thu 2024-10-03 10.30 - 11.30
Location: Faxén, Teknikringen 8
Participating: Prof. Ida Karimfazli (Concordia University, Montréal)
Abstract: As the accuracy and precision of computational simulations and experimental measurements improve, new questions arise about the adequacy of rheological models in predicting the behavior of non-Newtonian fluids. Yield stress fluids have traditionally been modeled as rigid until they begin to flow. The rheological models commonly used to predict their flow behavior are often viscoplastic, based on strain-rate-dependent functions fitted to flow curves. This talk will review experimental observations of buoyancy-driven flows of yield stress fluids and compare them to theoretical predictions derived from viscoplastic models, aiming to develop a unified understanding. To further explore this connection, time-resolved particle image velocimetry is used in an archetypal setup to characterize the onset and evolution of flow—or its absence. By comparing predictions with experimental observations, we can identify the limitations of current viscoplastic models and provide insights for the development of next-generation models for yield stress fluids.
Bio: Ida Karimfazli is an Associate Professor in the Department of Mechanical, Industrial & Aerospace Engineering at Concordia University. She received her master’s degree from Stanford University and PhD from University of British Columbia. She specializes in complex flow dynamics and heat transfer. Her research at Concordia University is dedicated to mitigating the environmental impact of the energy sector and advancing sustainable technologies. Most of her research projects are motivated by the applications of complex fluids in the development of clean technologies and renewable energy. She has established the Complex Fluids Research Group and Laboratory at Concordia University where she has been conducting theoretical, numerical and experimental research.