FEM Analysis of Thixo-Viscoplastic Flows

What is it about?

This research explores the use of the Finite Element Method (FEM) to model and simulate the behavior of thixotropic materials under viscoplastic flow conditions. Thixotropic materials are those whose viscosity decreases over time when under stress and recovers when the stress is removed. The study employs a quasi-Newtonian approach to generalize the Navier-Stokes equations for such materials, incorporating microstructural effects through a structure-dependent viscosity formulation. This new set of equations, referred to as thixo-viscoplastic (TVP) generalized Navier-Stokes equations, allows for the simulation of the unique flow characteristics of thixotropic materials, such as their shear thinning behavior and time-dependent viscosity. The research addresses two main flow configurations: Couette flow, which involves the flow of material between two rotating cylinders, and contraction flow, which looks at the flow through a sudden narrowing in the channel. These scenarios are critical for understanding how thixotropic materials behave in both simple and complex geometries, mimicking laboratory experiments and industrial applications. The developed FEM solver is robust, adapting to the challenges posed by the complex rheological behavior of thixotropic materials, and provides insights into the flow distribution near walls and the optimization of restart pressures in industrial processes.

Featured Image

Photo by Markus Spiske on Unsplash

Photo by Markus Spiske on Unsplash

Why is it important?

Understanding the flow behavior of thixotropic materials is essential for numerous industrial applications, including the processing of food, cosmetics, pharmaceuticals, and construction materials. The ability to accurately model and predict the flow of such materials can lead to more efficient processing techniques, better product quality, and lower manufacturing costs. The developed modeling approach and simulation tools offer a significant advancement in the field, enabling more accurate and comprehensive analysis of thixotropic flow problems. By providing detailed insights into the behavior of these materials under different flow conditions, the research can help in designing better equipment and processes that account for the unique properties of thixotropic materials. This is particularly relevant for industries where the precise control of material flow is crucial for product consistency and quality. KEY TAKEAWAY: The study introduces a robust FEM-based tool for simulating the complex flow behavior of thixotropic materials, enhancing industrial process design and efficiency.