Now showing items 39-54 of 54

    • Power Series for Normal Stress Differences of Polymeric Liquids in Large-Amplitude Oscillator Shear Flow 

      Poungthong, P.; Giacomin, A. Jeffrey; Saengow, Chaimongkol; Kolitawong, Chanyut (2018-04)
      Exact solutions for normal stress differences in polymeric liquids subjected to largeamplitude oscillatory shear flow (LAOS) contain many Bessel functions, each appearing in infinite sums. For the simplest relevant model ...
    • Power Series for Shear Stress of Polymeric Liquid in Large-Amplitude Oscillatory Shear Flow 

      Poungthong, P.; Saengow, Chaimongkol; Giacomin, A. Jeffrey; Kolitawong, Chanyut (2018-04)
      xact solutions for shear stress in a polymeric liquid subjected to large-amplitude oscillatory shear flow (LAOS) contain many Bessel functions. For the simplest of these, for instance, the corotational Maxwell fluid, in ...
    • Reflections on Inflections 

      Saengow, Chaimongkol; Giacomin, A. Jeffrey; Gilbert, Peter H.; Kolitawong, Chanyut (2015-11-11)
      In plastics processing, the single most important rheological property is the steady shear viscosity curve: the logarithm of the steady shear viscosity versus the logarithm of the shear rate. This curve governs the volumetric ...
    • Review of Nonlinear Oscillatory Shear Flow Notations and Presentations: Polymeric Liquids 

      Saengow, Chaimongkol; Giacomin, A. Jeffrey (2018-12)
      We review notations for, along with ways of presenting, the shear stress responses to large-amplitude oscillatory shear flow (LAOS). We find that the Fourier loss and storage viscosities to be the simplest primal notations ...
    • Series Expansion for Shear Stress in Large-Amplitude Oscillatory Shear Flow From Oldroyd 8-Constant Framework 

      Poungthong, P.; Giacomin, A. Jeffrey; Saengow, Chaimongkol; Kolitawong, Chanyut (2018-06)
      When polymeric liquids undergo large-amplitude oscillatory shear flow (LAOS), the shear stress responds as a Fourier series, the higher harmonics of which are caused by the fluid nonlinearity, and the first harmonic of ...
    • Simple Accurate Expressions for Shear Stress in Large-Amplitude Oscillatory Shear Flow 

      Saengow, Chaimongkol; Giacomin, A. Jeffrey; Khalaf, N.; Guay, Martin (2017-05)
      Analytical solutions for shear stress in large-amplitude oscillatory shear flow (LAOS), for continuum or molecular models, often take the form of the first few terms of a power series in the shear rate amplitude. For ...
    • Slip Heating in Die Drool 

      Gilbert, Peter H.; Giacomin, A. Jeffrey (2014-05-14)
      When molten plastic is extruded from a die, it can collect on the open die face. Called die drool, this phenomenon costs plastics manufacturers by requiring shutdown for die cleaning. This has been attributed to cohesive ...
    • Slip Heating in Die Drool with Viscous Dissipation 

      Gilbert, Peter H.; Giacomin, A. Jeffrey (2014-10-06)
      Plastics can build-up on the die lip during extrusion. This phenomenon is called die drool and can be costly for plastics producers, requiring periodic shutdowns for die cleaning. Die drool has been attributed to the ...
    • Startup Steady Shear Flow from the Oldroyd 8-Constant Framework 

      Saengow, Chaimongkol; Giacomin, A. Jeffrey; Grizutti, Nino; Pasquino, R. (2019-01)
      One good way to explore fluid microstructure, experimentally, is to suddenly subject the fluid to a large steady shearing deformation, and to then observe the evolving stress response. If the steady shear rate is high ...
    • Temperature Rise in a Verging Annular Die 

      Younes, Georges R.; Giacomin, A. Jeffrey; Gilbert, Peter H. (2015-12-07)
      Plastic pipes, tubes or catheters are extruded by pressure‑driven flows through annular dies. Whereas die lands are straight, the section connecting the die land to the extruder either converges or diverges, converging ...
    • Thermodynamic Instability of Polymeric Liquids in Large-Amplitude Oscillatory Shear Flow from Corotational Maxwell Fluid 

      Saengow, Chaimongkol; Giacomin, A. Jeffrey (2018-04)
      When polymeric liquids are subjected to oscillatory shear flow, if the amplitude of the shear rate is high enough, the shear stress response will become aperiodic. This has been variously attributed to fracture, common ...
    • Transport Phenomena in Eccentric Cylindrical Coordinates 

      Gilbert, Peter H.; Saengow, Chaimongkol; Giacomin, A. Jeffrey (2016-09)
      Studies in transport phenomena have been limited to a select few coordinate systems. Specifically, Cartesian, cylindrical, spherical, Dijksman toroidal, and bipolar cylindrical coordinates have been the primary focus of ...
    • Unidirectional Large-Amplitude Oscillatory Shear Flow of Human Blood 

      Saengow, Chaimongkol; Giacomin, A. Jeffrey; Dimitrov, Andrea S. (2019-09)
      Blood is non-Newtonian suspension of red and white cells, platelets, fibrinogen and cholesterols in Newtonian plasma. To assess its non-Newtonian behaviors, this work considers a newly proposed blood test, unidirectional ...
    • Van Gurp-Palmen Relations for Long-Chain Branching From General Rigid Bead-Rod Theory 

      Kanso, Mona A.; Giacomin, A. Jeffrey (2020-02)
      Empirically, we find that parametric plots of mechanical loss angle versus complex shear modulus may depend neither on temperature [van Gurp and Palmen, Rheol Bull (SoR), 67, 5 (1998)], nor on average molecular weight ...
    • Wall Slip Heating 

      Gilbert, Peter H.; Giacomin, A. Jeffrey (2015-01-05)
      When molten plastic is extruded, the upper limiting throughput is often dictated by fine irregular distortions of the extrudate surface. Called sharkskin melt fracture, plastics engineers spike plastics formulations with ...
    • πάντα ῥεῖ (Everything Flows): Motto for Rheology 

      Beris, Antony N.; Giacomin, A. Jeffrey (2014-05-23)
      This historical study deepens the rheologist’s understanding of the motto of The Society of Rheology, of its history, and of its many typographies. The motto “πάντα ῥεῖ” is not verbatim something written or said by the ...