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[Display omitted] Processing of electrode slurry, which is highly non-Newtonian fluid, is a critical step in the mass production of lithium-ion batteries (LIBs). While extensional flow plays an important role in the electrode slurry processes such as coating, most previous studies have focused only on the shear rheology, due to the lack of a reliable method to measure the extensional rheological properties of the slurry. Here, it is demonstrated that the extensional rheological properties of the anode slurries can be successfully characterized using the stop-flow-dripping-onto-substrate/capillary break-up rheometry (SF-DoS/CaBER). Using this system, it is observed that the extensional rheology of the anode slurry is significantly affected by the blend ratio of the natural and synthetic graphite, as well as the binder and conductive concentrations. Furthermore, the shear rheology-based model predicts much shorter pinch-off times than those measured experimentally, indicating that the yield-stress of the anode slurry is much larger in extensional flow than in shear flow. [ABSTRACT FROM AUTHOR]

[Display omitted] Achieving rapid capillary wetting is highly desirable in nature and industries. Previous endeavors have primarily concentrated on passive wetting strategies through surface engineering. However, these approaches are inadequate for high-viscosity fluids due to the significant viscous resistance, especially for non-Newtonian fluids. In contrast, forced wetting emerges as a promising method to address the challenges associated with achieving rapid wetting of non-Newtonian fluids in capillaries. To investigate the forced wetting behavior of viscoelastic fluids in capillaries, we employ Xanthan Gum (XG) aqueous solutions as target fluids with the storage modulus significantly exceeding the loss modulus. We utilize smooth glass capillaries connected to a syringe pump to achieve high moving speeds of up to 1 m/s. Our experiments reveal a significant distinction in the power-law exponent that governs the scaling relationship between the dynamic contact angle and velocity for viscoelastic fluids compared to Newtonian fluids. This exponent is considerably smaller and varies based on the concentration of viscoelastic fluids and the diameter of the capillaries. We suggest that the viscosity dominates the wetting dynamics of viscoelastic fluids, manifested by the contact line morphology-dependent behavior. This insight has significant implications for microfluidics and drug injectability. [ABSTRACT FROM AUTHOR]

We consider a non-Newtonian incompressible heat conducting fluid with a prescribed nonuniform temperature on the boundary and with the no-slip boundary condition for the velocity. We assume no external body forces. For the power-law like models with the power law index bigger than or equal to 11/5 in three dimensions, we identify a class of solutions fulfilling the entropy equality and converging to the equilibria exponentially in a proper metric. In fact, we show the existence of a Lyapunov functional for the problem. Consequently, the steady solution is nonlinearly stable and attracts all proper weak solutions. [ABSTRACT FROM AUTHOR]

We present and analyze a series of benchmark tests regarding the application of the immersed boundary (IB) method to viscoelastic flows through and around non-trivial, stationary geometries. The IB method is widely used to simulate biological fluid dynamics and other modeling scenarios in which a structure is immersed in a fluid. Although the IB method has been most commonly used to model systems involving viscous incompressible fluids, it also can be applied to visoelastic fluids and has enabled the study of a wide variety of dynamical problems including the settling of vesicles and the swimming of elastic filaments in fluids modeled by the Oldroyd-B constitutive equation. In the viscoelastic context, however, relatively little work has explored the accuracy or convergence properties of this numerical scheme. Herein, we present benchmarking results for an IB solver applied to viscoelastic flows in and around non-trivial geometries using either the idealized Oldroyd-B constitutive model or the more physically realistic, polymer-entanglement-based Rolie-Poly constitutive equations. We use two-dimensional numerical test cases along with results from rheology experiments to benchmark the IB method and compare it to more complex finite element and finite volume viscoelastic flow solvers. Additionally, we analyze different choices of regularized delta function and relative Lagrangian grid spacings which allow us to identify and recommend the key choices of these numerical parameters depending on the present flow regime. • The Immersed Boundary method is applied to viscoelastic flows around non-trivial, stationary geometries. • Computational results are compared to previous numerical benchmarks and macrorheology experiments. • Choices of relative Lagrangian grid spacings and delta functions are analyzed, with recommendations for current flow regimes. [ABSTRACT FROM AUTHOR]

In this study, soyasaponin (Ssa), corn oil, and soybean protein isolate (SPI) were used to prepare a water-in-oil-in-water (W/O/W) double emulsion system that can protect Lactobacillus plantarum (L.P) in the upper gastrointestinal tract for delivery to the small intestine and colon. Incorporating different amounts of L.P (0.1–0.6% (w/v)) in the W/O/W double emulsion caused the viscoelastic modulus and droplet size of the L.P-embedded emulsion system to change, and the emulsion system transformed from a non-Newtonian fluid to a "solid-like" gel. These results revealed that L.P encapsulation led to significantly improved stability of the W/O/W emulsion. In addition, different concentrations of L.P had different effects on the survival rate of L.P in simulated digestive fluids, and after in vitro digestion, L.P was naturally delivered from the stomach into the intestines. The optimal concentration of L.P for obtaining a stable emulsion was found to be 0.3%, and the survival rate of the encapsulated L.P in the small intestine was as high as 78.96% after 1 h. Thus, choosing an appropriate amount of L.P was crucial. The W/O/W emulsion system effectively maintained the viability of L.P and successfully delivered it to the small intestine and colon. • Ssa-SPI W/O/W emulsion improves the survival of LP in the gastrointestinal tract. • L.P shows better resistance to gastric acid upon encapsulation in inner phase. • Addition of 0.2–0.4% of L.P resulted higher stability in Ssa-SPI W/O/W emulsions. • The adsorption and film formation of L.P at the interface helps stabilize emulsion. [ABSTRACT FROM AUTHOR]