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Showing 1 to 9 of 9 for “"Oldroyd-B model"”.
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Complex fluid dynamical computations via the Finite Volume Method
… are investigated. The viscoelastic fluids are modelled, primarily, via the Johnson-Segalman constitutive model. Our Numerical approach is based on finite volume method, based on the Johnson-Segalman constitutive model and implemented on the OpenFOAM® platform. The Johnson-Segalman model also …
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Numerical Simulations of Viscoelastic Flows Using the Discontinuous Galerkin Method
… the Navier-Stokes equations coupled with the Oldroyd-B model. We solve the Navier-Stokes equations in skew-symmetric form using the mixed finite element method, and we solve the Oldroyd-B model using the discontinuous Galerkin method. The Crank-Nicolson scheme is used for the temporal …
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Simulation of nonisothermal and time-dependent viscoelastic flows
… develop constitutive equations appropriate for modeling nonisothermal viscoelastic flows and to examine the influence of temperature variations on the stress in the fluid. The pseudotime method developed by Crochet and Naghdi (1978) and by Sarti (1977) is used to obtain thermodynamically …
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Fluid Mechanics for Biomedical Applications: Weakly Viscoelastic Electrospray, Flow Focusing and Collapsible Channel Models
… phenomena implementing a 2D collapsible channel model. i) A systematic, theoretical comparison of a Newtonian fluid, and a non-Newtonian one modelled using an Oldroyd-B model was performed, resulting in a better understanding of how the properties of this type of material influence aspects such …
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Instability and Transition to Turbulence in Complex Viscoelastic Flows Overlying Porous Surfaces
… and wall permeability. A modified Darcy-Brinkman-Oldroyd-B model is developed to describe the flow behavior within and adjacent to porous media, incorporating fully coupled interfacial conditions between the free-fluid and porous domains. Using this framework, a comprehensive linear stability …
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Simulations of interfacial dynamics of complex fluids using diffuse interface method with adaptive meshing
… for manual intervention as in sharp-interface model to effect such event. Moreover, this energy-based formulation easily incorporates complex rheology as long as the free energy of the microstructures is known. The complex fluids considered in this thesis include viscoelastic fluids and nematic …
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The solution of large viscoelastic flow problems using parallel iterative techniques
… is stiff, assymmetric and indefinite. With this model problem, the preconditioner's robustness is tested and its efficiency is measured. The solver's generalizability for viscous flow problems is also discussed, as the only assumption about problem physics is that the continuity equation exists. …
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Simulation of blood flows in a stenosed and bifurcating artery using finite volume methods and OpenFOAM
… is human blood, a complex fluid which can be modelled via viscoelastic constitutive models. The most commonly used constitutive models for viscoelastic fluids include the OldroydB, Giesekus, Johnson-Segalman, Finitely Extensible Non-Linear Elastic (FENE), Phan-Thein-Tanner (PTT) models etc. …
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Modeling of three-dimensional viscoelastic flows with free surfaces using a finite element method
… have been conducted in this geometry with the Oldroyd-B model, [beta] = 0.67, wall separation distances between 4-32 radii, and Deborah number 0.1 < De < 2.0. The range of bounding wall edge effects on the flow field is shown to be just under 4 cylinder radii. At De = 2.0, the simulation shows …