Entry flows of Bingham plastics in expansions

Simulation of viscoelastic and viscoelastoplastic die-swell flows

“…As s o increases, the progressive growth of the unyielded regions is quite apparent, which is entirely consistent with findings reported by others [29,30,16].…”

On the Numerical Simulation of Viscoplastic Fluid Flow

“…The first approach relies on regularization; it has been widely used for many years by many practitioners (see, among many others, Beris, Tsamopoulos, Armstrong and Brown [1985], Papanastasiou [1987], Abdali, Mitsoulis and Markatos [1992], Mitsoulis, Abdali and Markatos [1993], Burgos and Alexandrou [1999], Mitsoulis and Zisis [2001], Liu, Muller and Denn [2002], and Mitsoulis and Huilgol [2004]). The key idea behind regularization methods is to approximate the (nonsmooth) constitutive law by a differentiable one.…”

A numerical investigation of inertia flows of Bingham-Papanastasiou fluids by an extra stress-pressure-velocity galerkin least-squares method

“…Figure 4 shows details in the expansion vicinity of the selected mesh (M2) with 19,800 elements and 121,686 degrees-of-freedom. (6)) equal to 1000 s, following some viscoplastic works (see, for instance, Mitsoulis and Huilgol (2004)). In order to obtain the dimensionless groups that govern the viscoplastic fluid flow, Eq.…”

“…The authors concluded that the increasing of Bingham number leads to a significant pressure drop increase, due to the growth of unyielded material regions throughout the expansion channel. This geometry is also considered by Mitsoulis and Huilgol (2004) in the simulation of entry flows of Bingham fluids via finite element method, ranging Bingham and Reynolds numbers to take into account yield-stress and inertia effects, respectively. Roquet and Saramito (2007) used an anisotropic and self-adaptive finite element method, to simulate Pouseuille flow of Bingham fluids through square ducts, imposing slip boundary conditions on walls and identifying different flow regimes.…”