Implementation and comparison of turbulence models on a flat plate problem using a Navier-Stokes solver

Download
2003
Genç, Balkan Ziya
For turbulent flow calculations, some of the well-known turbulence models in the literature are applied on a previously developed Navier-Stokes solver designed to handle laminar flows. A finite volume formulation, which is cell-based for inviscid terms and cell-vertex for viscous terms, is used for numerical discretization of the Navier-Stokes equations in conservative form. This formulation is combined with one-step, explicit time marching Lax-Wendroff numerical scheme that is second order accurate in space. To minimize non-physical oscillations resulting from the numerical scheme, second and fourth order artificial smoothing terms are added. To increase the convergence rate of the solver, local time stepping technique is applied. Before applying turbulence models, Navier-Stokes solver is tested for a case of subsonic, laminar flow over a flat plate. The results are in close agreement with Blasius similarity solutions. To calculate turbulent flows, Boussinesq eddy-viscosity approach is utilized. The eddy viscosity (also called turbulent viscosity), which arises as a consequence of this approach, is calculated using Cebeci-Smith, Michel et. al., Baldwin-Lomax, Chien2s k-epsilon and Wilcox2s k-omega turbulence models. To evaluate the performances of these turbulence models and to compare them with each other, the solver has been tested for a case of subsonic, laminar - transition fixed - turbulent flow over a flat plate. The results are verified by analytical solutions and empirical correlations.

Suggestions

Implementation and assessment of Hellsten explicit algebraic Reynolds stress k-omega model
İlhan, Umut; Aksel, Mehmet Haluk; Baran, Özgür Uğraş; Department of Mechanical Engineering (2022-9)
Turbulence modeling is one of the most challenging aspects of Computational Fluid Dynamics (CFD). The choice of turbulence model affects the accuracy and computational cost of the CFD analyses. Linear Eddy Viscosity Models (LEVMs) are commonly used in industrial CFD applications due to their low computational cost and ease of convergence. However, they often fail to model complex flow structures. More advanced models, such as Reynolds Stress Transport Models (RSTMs), have better performance for capturing th...
AN IMPROVED 1D MODEL FOR LIQUID SLUGS TRAVELLING IN PIPELINES
Tijsseling, Arris S.; Hou, Qingzhi; Bozkuş, Zafer (2014-07-24)
An improved one-dimensional (1D) model - compared to previous work by the authors - is proposed which is able to predict the acceleration and shortening of a single liquid slug propagating in a straight pipe with a downstream bend. The model includes holdup at the slug's tail and flow separation at the bend. The obtained analytical and numerical results are validated against experimental data. The effects of the improvement and of holdup are examined in a parameter variation study.
Experimental investigation of waveform tip injection on the characteristics of the tip vortex
Ostovan, Yashar; Uzol, Oğuz; Department of Aerospace Engineering (2011)
This study investigates the effect of chordwisely modulated tip injection on the flow and turbulence characteristics of the tip vortex through experimental measurements downstream of a rectangular half-wing that has an aspect ratio of three. This injection technique involves spanwise jets at the tip that are issued from a series of holes along the chord line normal to the freestream flow direction. The injection mass flow rate from each hole is individually controlled using computer driven solenoid valves a...
Applications of a 3-D numerical model to circulation in coastal waters
Balas, L; Ozhan, E (2001-06-01)
A three dimensional baroclinic numerical model which consists of hydrodynamic, transport and turbulence model components, has been applied to two test cases, including: the wind induced flow in a laboratory basin and tidal flow in a model rectangular harbor. The agreement between the physical and numerical model results is highly encouraging. Model has been implemented to Oludeniz Lagoon located at the Mediterranean coast of Turkey to simulate tidal and wind driven currents. M2 tide is the dominant tidal co...
An Improved One-Dimensional Model for Liquid Slugs Traveling in Pipelines
TIJSSELING, Arris S.; Hou, Qingzhi; Bozkuş, Zafer (2016-02-01)
An improved one-dimensional (1D) model-compared to previous work by the authors-is proposed, which is able to predict the acceleration and shortening of a single liquid slug propagating in a straight pipe with a downstream bend. The model includes holdup at the slug's tail and flow separation at the bend. The obtained analytical and numerical results are validated against experimental data. The effects of holdup, driving pressure and slug length are examined in a parameter variation study.
Citation Formats
B. Z. Genç, “Implementation and comparison of turbulence models on a flat plate problem using a Navier-Stokes solver,” M.S. - Master of Science, Middle East Technical University, 2003.