Occurrence of laminar separation bubbles on solid walls of an elliptic cylinder has been simulated using a recently developed transitional model for boundary layer flows. Computational method is based on the solution of the Reynolds averaged Navier-Stokes (RANS) equations and the eddy-viscosity concept. Transitional model tries to simulate streamwise fluctuations, induced by freestream turbulen...

In this research we have implemented the Random Vortex Method to calculate velocity fields of fluids inside open cavities in both turbulent and laminar flows. the Random Vortex Method is a CFD method (in both turbulent and laminar fields) which needs the Schwarz-Christoffel transformation formula to map the physical geometry into the upper half plane. In some complex geometries like the flow in...

The airflow in the modeled glottal constriction was simulated by the solutions of the Navier-Stokes equations for laminar flow, and the corresponding Reynolds equations for turbulent flow in generalized, nonorthogonal coordinates using a numerical method. A two-dimensional model of laryngeal flow is considered and aerodynamic properties are calculated for both laminar and turbulent steady flows...

Using the highly recommended numerical techniques, a finite element computer code is developed to analyse the steady incompressible, laminar and turbulent flows in 2-D domains with complex geometry. The Petrov-Galerkin finite element formulation is adopted to avoid numerical oscillations. Turbulence is modeled using the two equation k-ω model. The discretized equations are written in the form o...

Using the highly recommended numerical techniques, a finite element computer code is developed to analyse the steady incompressible, laminar and turbulent flows in 2-D domains with complex geometry. The Petrov-Galerkin finite element formulation is adopted to avoid numerical oscillations. Turbulence is modeled using the two equation k-ω model. The discretized equations are written in the form o...

Alternating laminar and turbulent helical bands appearing in shear flows between counterrotating cylinders are accurately computed and the near-wall instability phenomena responsible for their generation identified. The computations show that this intermittent regime can only exist within large domains and that its spiral coherence is not dictated by endwall boundary conditions. A supercritical...

The magnetic Reynolds number RM , is defined as the product of a characteristic scale and associated flow speed divided by the microphysical magnetic diffusivity. For laminar flows, RM also approximates the ratio of advective to dissipative terms in the total magnetic energy equation, but for turbulent flows this latter ratio depends on the energy spectra and approaches unity in a steady state....

In this paper, the Al2O3-water nanofluid flow in laminar and turbulent flows inside tubes fitted with diamond-shaped turbulators is numerically modeled. The nanofluid flow is modeled by employing a two-phase mixture method and applying the constant heat flux boundary condition at tube walls. In the results, the effects of different parameters such as the geometry of turbulators, volume fraction...

The magnetic Reynolds number RM , is defined as the product of a characteristic scale and associated flow speed divided by the microphysical magnetic diffusivity. For laminar flows, RM also approximates the ratio of advective to dissipative terms in the total magnetic energy equation. However, for turbulent flows this latter ratio depends on the energy spectra and approaches unity in a steady s...

Prior to the 2001 CMER pilot study, several TFW cooperators conducted independent field studies of the distribution of perennial and seasonal headwater streams (Table 1). All of the studies were conducted during the summer low flow seasons of 1998 or 2000, in part, to evaluate proposed regulatory guidelines that differentiate non-fish-bearing headwater streams on the basis of the seasonal flow ...