21 research outputs found

    On Predicting The Turbulence-induced Secondary Flows Using Nonlinear K-∈ Models

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    Low turbulent Reynolds number direct simulation data are used to calculate the invariants of the Reynolds stress and the turbulent dissipation rate in a square duct. The results show that, depending on the region where the analysis is carried out, the turbulent flow field comes close to one-, two-, and three-component states. Modeling such flows - even at higher Reynolds numbers - will require models that can approach all three states. A number of related nonlinear k-∈ models are tested a priori using the direct simulation data. The numerical simulation using Reynolds averaged Navier-Stokes equations with these models was performed. Their ability to predict the secondary flows, with a low-Reynolds k-∈ model, cannot be gauged from realizability. © 1996 American Institute of Physics.8718561868Speziale, C.G., Analytical methods for the developments of Reynoldsstress closures in turbulence (1991) Annu. Rev. Fluid Mech., 23, p. 107Speziale, C.G., On non-linear k-l and k-∈ models of turbulence (1987) J. Fluid Mech., 178, p. 459Joseph, D.D., (1984) Fluid Dynamics of Viscoelastic Liquids, , Springer-Verlag, New YorkShih, T., Zhu, J., Lumley, J.L., (1993) A Realizable Reynolds Stress Algerbraic Equation Model, , NASA Tech. Memo TM-105993Rubinstein, R., Barton, J.M., Nonlinear Reynolds stress models and the renormalization group (1990) Phys. Fluids A, 8, p. 1472Demuren, A.O., Rodi, W., Calculation of turbulence-driven secondary motion in non-circular ducts (1984) J. Fluid Mech., 140, p. 189Gatski, T.B., Speziale, C.G., On explicit algebraic stress models for complex turbulent flows (1993) J. Fluid Mech., 254, p. 59Pope, S.B., A more general effective-viscosity hypothesis (1975) J. Fluid Mech., 72, p. 331Huser, A., Biringen, S., Hatay, F.F., Direct simulation of turbulent flow in a square duct: Reynolds-stress budgets (1994) Phys. Fluids, 6, p. 3144Gibson, M.M., Launder, B.E., Ground effects on pressure fluctuations in the atmospheric boundary layer (1979) J. Fluid Mech., 86, p. 491Cheesewright, R., McGrath, G., Petty, D.G., (1990) LDA Measurements of Turbulent Flow in a Duct of Square Cross Section at Low Reynolds Number, , Aeronautical Engineering Department, University of London, Report No. ER 101Huser, A., Biringen, S., Direct numerical simulation of turbulent flow in a square duct (1993) J. Fluid Mech., 257, p. 65Gavrilakis, S., Numerical simulation of low-Reynolds-number turbulent flow through a straight square duct (1992) J. Fluid Mech., 244, p. 101Gavrilakis, S., (1993) Turbulent Velocity Structures Derived from POD Analyses, , Institute de Machines Hydrauliques et de Mécanique des Fluides, École Polytechnique Fédérale de Lausanne, Report No. T-93-30Antonia, R.A., Kim, J., Browne, L.W.B., Some characteristics of small-scale turbulence in turbulent duct flow (1991) J. Fluid Mech., 233, p. 369Bradshaw, P., Blair Perot, J., A note on turbulent energy dissipation in viscous wall region (1993) Phys. Fluids, 5, p. 3305Kim, J., Moin, P., Moser, R., Turbulent statistics in fully developed channel flow at low Reynolds number (1987) J. Fluid Mech., 177, p. 133Tennekes, H., Lumley, J.L., (1972) A First Course in Turbulence, , MIT Press, Cambridge, MALumley, J.L., Computational Modeling of Turbulent Flows (1978) Advances in Applied Mechanics, 18, p. 123. , Academic Press. New YorkGavrilakis, S., Large-scale structures in the turbulent flow near a right-angled corner (1994) 1st ERCOFTAC Workshop on Direct and Large-Eddy Simulation, , SurreyGessner, F.B., The origin of secondary flow in turbulent flow along a corner (1973) J. Fluid Mech., 58, p. 1Speziale, C.G., The dissipation rate correlation and turbulent secondary flows in noncircular ducts (1986) Trans. Am. Soc. Mech. Eng. J. Fluid Eng., 108, p. 118Durbin, P.A., Near-wall turbulence closure modeling without damping functions (1991) Theor. Comput. Fluid Dyn., 3, p. 1Rodi, W., Mansour, N.N., Low Reynolds number k-∈ modeling with the aid of direct simulation (1993) J. Fluid Mech., 250, p. 509Mompean, G., Three-equation turbulence model for prediction of the mean square temperature variance in grid-generated flows and round jets (1994) Int. J. Heat Mass Transfer, 37, p. 1165Chien, K.Y., Prediction of channel and boundary-layer flows with a low-Reynolds-number turbulence model (1982) AIAA J., 20, p. 33Lam, C.K.G., Bremhorst, K., A modified form of the k-∈ model predicting wall turbulence (1981) Trans. Am. Soc. Mech. Eng. J. Fluid. Eng., 103, p. 456Reynolds, W.C., Computation of turbulent flows (1976) Annu. Rev. Fluid Mech., 8, p. 183Lindberg, P.A., (1994), private communicationNisizima, S., A numerical study of turbulent square-duct flow using an anisotropic k-∈ model (1990) Theor. Comput. Fluid Dyn., 2, p. 61Launder, B.E., Tselepidakis, D.P., Contribution to the modelling of near-wall turbulence (1993) Turbulent Shear Flows 8, p. 81. , edited by F. Durst, R. Friedrich, B. E. Launder, F. W. Schmidt, and J. H. Whitelaw, MunichNaimi, N., Gessner, F.B., A calculation method for developing turbulent flow in rectangular ducts of arbitrary aspect ratio (1995) J. Fluid Eng., 117, p. 249Launder, B.E., Reece, G.J., Rodi, W., Progress in the development of a Reynolds-stress turbulence closure (1975) J. Fluid Mech., 68, p. 537Hanjalic, K., Launder, B.E., A Reynolds stress model of turbulence and its application to thin shear flows (1972) J. Fluid Mech., 52, p. 60

    Mesh update techniques for free-surface flow solvers using spectral element method

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    This paper presents a novel mesh-update technique for unsteady free-surface Newtonian flows using spectral element method and relying on the arbitrary Lagrangian--Eulerian kinematic description for moving the grid. Selected results showing compatibility of this mesh-update technique with spectral element method are given

    Large-eddy simulation of the lid-driven cubic cavity flow by the spectral element method

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    This paper presents the large-eddy simulation of the lid-driven cubic cavity flow by the spectral element method (SEM) using the dynamic model. Two spectral filtering techniques suitable for these simulations have been implemented. Numerical results for Reynolds number Re=12′000\text{Re}=12'000 are showing very good agreement with other experimental and DNS results found in the literature

    [An alternating direction implicit algorithm for viscous free surface flows]

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    The numerical integration of the Navier-Stokes equations for free surface flows, by a Douglas-Rachford modified alternating direction implicit scheme is considered. For slow flows of a weakly dissipative fluid, unconditional stability is shown by using a matrix method. Numerical results for confined flows are presented for the square cavity problem and the shear flow of a dissipative fluid. The free surface algorithm rests upon two stages: a prediction step and a correction step, and is applied to the study of the surge front of a collapsing fluid column.Francai

    Chebyshev collocation method and multi-domain decomposition for Navier-Stokes equations in complex curved geometries

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    A general multidomain decomposition is proposed for the numerical solution of the 2D incompressible stationary Navier-Stokes equations. The solution technique consists in a Chebyshev orthogonal collocation method preconditioned by a standard Galerkin finite element technique. The preconditioned system is then solved through a Richardson procedure. The domain of interest is decomposed into quadrilaterals, curved when needed. A Gordon transfinite interpolation performs the curvilinear grid generation of the obtained simply-connected planar subdomains. The interface conditions, naturally incorporated into the finite element approach, relate neighbour subdomains through the normal jump of appropriate fluxes across internal boundaries, where an integral form of /b C//sup 1/ continuity is consequently achieved at convergence of the iterative processes. The study of model Stokes problems demonstrates that the current method still behaves spectrally in distorted geometries. For curvilinear distortion, a loss of several orders of magnitude is observed in the solution accuracy even when the distortion is very limited. Finally, some results of flow simulation in a constricted channel are proposed to illustrate the abilities of the method to treat Navier-Stokes problems.Anglai

    Chebyshev pseudospectral solution of the Stokes equations using finite element preconditioning

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    The Stokes equations are solved by a Chebyshev pseudospectral method on a rectangular domain. As the resulting system of algebraic equations is very difficult to factorize, a preconditioning is designed using a finite element technique. The FEM solver constitutes the masterpiece of a Richardson iteration process. Several finite elements are investigated: the 9-nodes Lagrangian element /b Q/2-/b Q/1, the /b Q/1-/b Q/0 element, and the /b Q/1-/b Q/1 element due to Brezzi and Pitkaranta. An eigenvalue analysis is carried out in order to pinpoint the characteristic features of each precondition. It is shown that the /b Q/2-/b Q/1 element yields the best convergence results. The power of this choice is demonstrated on theoretical solutions and on the regularized square cavity problem.Anglai

    On a Stable Spectral Method for the -grad(div) Eigenvalue Problem

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