Laminar mixed convection in a horizontal annular duct. Case of thermodependent non-Newtonian fluid

On the Numerical Simulation of Viscoplastic Fluid Flow

“…Indeed, computational viscoplasticity seems to have reached a turning point where, the basic computational methods being well understood (despite the fact that there is still room for progress for incompressible single-phase flows, such as speeding up the convergence of the solution algorithms), many practitioners are eager to consider more complex and realistic situations. In that direction, let us mention Mitsoulis, Abdali and Markatos [1993], Zenaidi [1998], Nouar, Benaouda-Zouaoui andDesaubry [2000], Vinay, Wachs and Agassant [2005], Zhang, Vola and Frigaard [2006] for flow with heat transfer; Dimakopoulos and Tsamopoulos [2003], Vola, Babik and Latché [2004] for free surface flows; Davidson, Nguyen, Chang and Ronningsen [2004], Vinay, Wachs and Agassant [2006] for compressible flows; and Dean, Glowinski and Pan [2003], Yu and Wachs [2007] for particulate flows.…”

“…The objective of this first study is to obtain the description of the flow pattern, when a yield stress fluid flows through a pipeline and cools down due to temperatures on the pipeline external boundary, which are lower than the inlet temperature; the yield stress temperaturedependent case will be of particular interest. Concerning the temperature dependence of the rheological parameters, let us mention that in Zenaidi [1998], Nouar, Benaouda-Zouaoui andDesaubry [2000], one has investigated, computationally and experimentally, the thermal convection phenomena for non-Newtonians fluids in a horizontal annular duct. However, in the above publications, only the temperature dependence of the viscosity coefficient has been taken into account.…”

Forced convection to laminar flow of liquid egg yolk in circular and annular ducts

“…Based on their numerical results, they proposed an expression for the Nusselt number, which was a function of κ, n, Re, Gz and Gr; their experimental results and the proposed equation agree within 15 %. In the experimental tests of Nouar et al (2000) ≤ ≤ . The two cylinders of the test cell were heated by passing an electrical current through the tube wall, and their test section was covered by a thick polyurethane layer.…”

“…For Power-Law flows, investigations are almost reduced to the case of hydrodynamic and thermal fully developed conditions, and the solutions of the problem are basically obtained through finitedifference techniques, except for the works of Tanaka and Mitsuishi (1975) and Nouar et al (2000); the former not only analyzed numerically but also experimentally the problem of combined forced and free convection in the thermal entrance of a fully developed laminar flow in a horizontal annulus under the conditions of a constant-temperature inner wall and an insulated outer wall, whereas the latter considered the outer and inner cylinders uniformly heated with a constant heat flux density. The relatively recent studies of Manglik and Fang (2002) and Manglik and Fang (1995) considered the forced convection heat transfer in eccentric annular ducts with an insulated outer surface and uniform axial heat flux or constant wall temperature for the inner surface.…”

Heat transfer coefficients for the laminar fully developed flow of viscoplastic liquids through annuli

“…Among other findings, the authors concluded that the convective coefficient changed with the variations of the consistency index of the fluid. Nouar et al [18] also investigated both numerical and experimentally the influence of rheological parameters on the performance of the mixed-convection heat transfer process during the flow of a power-law fluid through the thermal entrance region of annuli. Manglik and Fang [19,20] analyzed the effect of the eccentricity and the behavior index for different diameter ratios and an insulated outer tube, with a thermally active inner tube (both uniform wall temperature and uniform wall heat flux).…”