A convective weakly viscoelastic rotating flow with pressure Neumann condition

• Published in: International journal for numerical methods in fluids Vol. 60; no. 3; pp. 295 - 322
• Main Authors: Claeyssen, Julio R., Asenjo, Elba Bravo, Rubio, Obidio
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 30.05.2009; Wiley
• Subjects: Computational methods in fluid dynamics; Convection and heat transfer; Exact sciences and technology; finite differences methods; Fluid dynamics; Fundamental areas of phenomenology (including applications); Hydrodynamic stability; incompressible flow; mixed convection; non-Newtonian; Non-newtonian fluid flows; Physics; pressure Neumann condition; rotating flow; Secondary instability; Turbulent flows, convection, and heat transfer; Rectangular pipe; Viscoelastic fluid; Rotating flow; Computational fluid dynamics; incompressible flow; Digital simulation; Boundary conditions; pressure Neumann condition; Rotating pipe; Combined convection; Algorithms; finite differences methods; mixed convection; Modelling; non-Newtonian; Incompressible fluid; Secondary flow; Mesh generation; Heat transfer; Finite difference method
• ISSN: 0271-2091; 1097-0363
• DOI: 10.1002/fld.1888

The objective of this work is to investigate through the numeric simulation, the effects of the weakly viscoelastic flow within a rotating rectangular duct subject to a buoyancy force due to the heating of one of the walls of the duct. A direct velocity–pressure algorithm in primitive variables with a Neumann condition for the pressure is employed. The spatial discretization is made with finite central differences on a staggered grid. The pressure field is directly updated without any iteration. Numerical simulations were done for several Weissemberg numbers (We) and Grashof numbers (Gr) . The numerical results show that for high Weissemberg numbers (We>7.4 × 10−5) and for ducts with aspect ratio 2:1 and 8:1, the secondary flow is restabilized with a stretched double vortex configuration. It is also observed that when the Grashof number is increased (Gr>17 × 10−4) , the buoyancy force neutralizes the effects of the Coriolis force for ducts with aspect ratio 8:1. Copyright © 2008 John Wiley & Sons, Ltd.